Down Syndrome By Kok Siong Chen

Down syndrome is a common genetic chromosomal syndrome among the population in the world. It is about 1 in 800 liveborns in the population with Down syndrome. This syndrome is starts to be described by a physician named John Langdon Down who published an article in 1866. He stated that there are some children with common characteristics but distinct from other children with mental retardation. He described this syndrome as "Mongoloids". He used this unfortunate name just because of those children looked like people from Mongolia. The "Mongoloids" was dropped from scientific use since 1960s to stop the ethic insult.

About 95% of all patients with Down syndrome have a 47, +21 karyotype. Among these cases there is a small group with familial translocation involving a chromosome 21 and another chromosome with balanced rearrangement. There are some very rare instances of direct transmission of the additional 21 from a Down syndrome mother or father to a Down syndrome child.

Down syndrome patient looks almost alike to each other. We can simply identify the Down syndrome patient by just looking to their physical outlook. However, a confident clinical diagnosis might be difficult early after birth, especially in prematures. Some of the useful diagnostic signs are brachycephaly (flat-head), small ears, Brushfield spots (brown spots on the periphery of the iris) and low iliac and acetabular index in pelvic radiographs. Congenital malformations are frequent in Down syndrome patients too. Thyroid dysfunction is also significantly associated with Down syndrome and might be the cause for developmental delay. Mentally retardation is the most common feature among the Down syndrome patients.

Generally, female menarche occurs at normal time and pregnancies are common among the Down syndrome patients. However, there is hypogenitalism and hypogonadism among the male patients. Therefore, the male with Down syndrome usually is infertile.

In conclusion, Down syndrome patients need to be taken care as there are various specific problems throughout their life. I will write more about the guideline for optimal medical care on these Down syndrome patients later.

Kok Siong Chen - blog about Cytogenetics and Cancer Research. Visit the blog or subscribe via EMAIL to get more about Cancer Research.

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Downs Syndrome Poses Obesity Risk By Phillip Longmire

Having a wife that works with life skill students I know there are all type of problems that arise with special needs students. Its sad because with students and or adults who have special needs will struggle with those needs their entire life, and now obesity seems to be just one more issue. I'm not sure there is an answer to this problem, but it seems that those who have Down's Syndrome posse obesity risk.

If your not sure what Downs Syndrome is, let me give you a working definition. It is a congenital disorder, caused by the presence of an extra 21st chromosome, in which the affected person has mild to moderate mental retardation, short stature, and a flattened facial profile. Also called trisomy

New research has shown that people who suffer from Down's Syndrome are more likely to become obese than those who do not have the condition.

Using families which had both children who had Down's Syndrome and brothers or sisters who did not, scientists were able to ensure that eating patterns offered by parents were very similar and that lifestyle choices and habits accrued as adults would not interfere with the study.

Monitoring 35 children with Down's Syndrome and 33 of their siblings who were free of the condition, researchers from The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine found that the Down's children had significantly higher body mass index and a higher percentage of body fat.

It was discovered that Down's Syndrome children had higher levels of leptin, a hormone linked to obesity, than their unaffected siblings. "The normal role of leptin is to suppress appetite and regulate body weight," explained senior author Dr Nicolas Stettler in the Jouranl of Paediatrics. "In general, obese people have higher levels of leptin, which suggests that they have some leptin resistance - their bodies do not respond to the hormone properly. Because Down's Syndrome is a chromosome disorder, children with Down's Syndrome may have a genetic predisposition to more severe leptin resistance."

Co-author Dr Sheela N Magge added: "Although the study had an advantage in including siblings as a control group, because this decreases the influence of different environments on children with or without Down's Syndrome, the sample size was limited, so larger studies are necessary. However, our findings may point to a useful approach to understanding why obesity often occurs in Down's Syndrome."

Around 60,000 people in the UK have Down's Syndrome and various charities have produced information for people with learning difficulties to advise them about making healthy eating choices which could help until more research is carried out.

I think as we advance in the fight against obesity and realize the effects it has, perhaps in the future this could be one less thing that people with special needs will have to battle. Because it seems in the earlier stages that people with Down's Syndrome poses obesity risk.

Phillip Longmire has a business degree and is the creator of fitness village [http://fitnessvillage.wordpress.com], a Blog dedicated to those trying to lose weight. He not only transformed his own life but is dedicated to helping others lose weight and live healthier lives.

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People With Down Syndrome Are Not Severely Handicapped By Mike Selvon

Until recently, people with Down syndrome were considered severely handicapped. Yet with better advocacy and pushes toward educational integration, adults with Down syndrome are getting married, working jobs, living independently and living well into their fifties.

Few people can forget the lovable character "Corky" on the hit TV series "Life Goes On," and how he constantly challenged stereotypes and unfair assumptions about those with such a disability. Advances in medicine, social normalization and the expansion of programs to help the disabled are credited with what is sometimes referred to as "the new generation" of Down syndrome.

People who are afflicted with this disability encounter many physical challenges that others do not. Their motor skill development is slow, so they will learn to breastfeed, roll over, walk and talk, as well as teeth later than other children their age. This can be frustrating for both the Down syndrome child and the parents who are repeatedly confronted with their own mistaken expectations.

Another physical risk is, of course, the associated health problems. Many babies with Down syndrome undergo heart, ear and eye surgeries before one year of age. There are later risks of epilepsy, obesity, heart disease, ear infections, thyroid disease, throat infections, pneumonia and osteoarthritis.

Everyday activities can be difficult for people with Down syndrome to cope with. Many disabled children are naturally empathetic and in tune with their parents emotions and they sense the frustration or stress the parents sometimes experience. The extra attention expected of parents is sometimes exhausting and overwhelming, so psychologists recommend that parents attend Down syndrome support meetings to talk to other parents who have Down syndrome children and learn new techniques for raising their disabled child.

One of the things that people with Down syndrome still struggle with is public misperceptions about their condition. For instance, they are often stereotyped as being always happy or "out of it," when in reality Down syndrome children experience a full range of emotions and have quite unique personality traits. However, there are certain coping strategies that work better. For example, routine and order help them control their lives better.

Additionally, self-talk helps them communicate, express themselves and make sense of what's going on. People with learning disabilities generally rebuke change, which has led to the misperception that they are stubborn by nature. Perhaps they are simply trying to understand what's going on and maintain control in their lives. Perhaps they just need a little extra patience from those around them.

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Just What is Downs Syndrome? By David Cowley

It's unfortunate that many people today just don't have the proper understanding of Downs Syndrome and what exactly this means. Some make wrong assumptions about those with this condition, their abilities, and their intelligence level. It's true that many with Downs Syndrome have typically lower than average cognitive abilities, but only a very small percentage of those with this condition are impaired enough to need constant supervision or to keep them from functioning on their own.

The actual condition itself is caused by a disorder of the chromosomes, with all or part of an extra twenty-first chromosome. There are some physical characteristics that are common among those with Downs Syndrome, including almond-shaped eyes caused by a fold in the eyelids. Some also have a particular type of crease on the hands, shorter limbs than average, poorer muscle tone than average, and a protruding tongue. Those with Downs Syndrome are often easy to spot because of these physical characteristics, but rarely do any of those with this condition have physical abnormalities that would keep him or her from functioning in normal circumstances. There is also an increased risk for heart defects, acid reflux disease, ear infection, sleep apnea, and often thyroid disease or disorders. Other than these conditions, those with Downs Syndrome rarely have any type of severe physical limitations or concerns.

This condition is different for everyone that has it in severity and limitations. However, most of those with Downs Syndrome are able to be integrated into public schools, sports, and the workplace. They may have certain limitations when it comes to their understanding of complex concepts but typically can handle money and a budget, manage their own apartment or home, and can also care for a baby when needed. The majority of those with this condition can care for themselves and their family as well as anyone else.

It's very shortsighted to assume that anyone with Downs Syndrome is severely disabled or unable to function or make decisions on his or her own. Again, this condition affects each patient differently, but the vast majority is just as functioning as anyone else.

Some years ago there was a very popular television series that revolved around a young man with Downs Syndrome, his family, and his schooling. They portrayed how successful he was in fitting in with other classmates, making decisions about his own activities, and even in running for class president. The TV series was very realistic about his limitations as well, but was an honest portrayal of what it's like to have this condition. Anyone with Downs Syndrome should be considered as capable and functioning as anyone else, and should be given every chance to succeed.

DO NOT GIVE CALCIUM SUPPLEMENTS. It is believed that large unused quantifies of calcium inn the downs syndrome fetus was a major contributing factor in causing the health related problems. Common Vitamins and over the counter products may help with Downs Syndrome.

Boron is known as the calcium helper and assists calcium absorption and utilization in the body.

Vitamin E promotes the natural body healing mechanism and oxygen to the heart and other muscles in the body. In addition it improves circulation.

Ginkgo is needed for the proper functioning of the vascular system and for improving blood circulation to the brain.

Vitamin B is known to help maintain the normal vasodilatation.

Amino Acid helps regulate growth, digestion and maintaining the body's immune system.

Oat Bran helps to regulate blood glucose levels, aids in lowering cholesterol, and helps in the removal of toxins.

Vitamin C is essential for defending the body against pollution and infections and enhances the immune system.

Always consult your doctor before using this information.

This Article is nutritional in nature and is not to be construed as medical advice.

David Cowley has created numerous articles about the relationship between diseases and vitamins. Visit Health Related Articles Article Source: http://EzineArticles.com/?expert=David_Cowley

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Is There a Link Between Folic Acid and Down Syndrome? By Henri K. Junttila

In past years, research has shown that folic acid can help in the prevention of neural-tube birth defects in unborn children. Babies have been born with part of their brain missing, called anencephaly, or with the medical condition spina bifida, in which the spine is actually on the outside of the body.

These are horrifying defects for expectant parents to think of. There are also studies that suggest a lack of vital nutrition during pregnancy is a factor in children being born with Down syndrome as well. What is the link between folic acid and Down Syndrome?

When there is trouble in the metabolism of folic acid, the occurrence of birth defects is far greater. Those babies born to these mothers have been more likely to be born with medical issues and defects.

Down Syndrome may be one of these as well. In these cases, it is even more unfortunate that the human body doesn't manufacture its own supply of this precious B vitamin. Because of this, a supplement of especially folic acid is essential during pregnancy.

Down's Syndrome occurs in children when the chromosome division goes wrong before egg fertilization. Usually, chromosomes come in pairs. There are 23 pairs.

One is from the mother's egg and one is from the father's sperm. In the cases of Down's Syndrome, there is an extra chromosome number 21. Why this one is affected is unclear. However, that will leave 47 chromosomes instead of the normal number of 46. The result is that unborn developing Down's Syndrome.

The addition of folic acid in mothers before and during pregnancy has been successful in the prevention of birth defects. Recent studies have also shown that Down's Syndrome may also be prevented with additional supplementation of this folate.

The best way to get folic acid is through a supplement. Because of how we must cook and store our food, the nutrients levels are greatly reduced, especially in the case of complex B vitamins.

If you are planning to get pregnant or have learned that you already are, then you must make sure that you get an adequate supplement of this important folate into your diet.

Most doctors prescribe a high nutrient prenatal multivitamin for this reason. Mothers should make it a point to take these every day and eat the foods that contain this nutrient.

The exact link between folic acid and Down's Syndrome remains a mystery, but the best thing to do is to make sure that you take a supplement to increase the chances of your unborn child not being affected by neural-tube defects.

If you are pregnant, please contact your doctor before you start any supplementation. If you aren't pregnant, I highly recommend you go with the best natural multivitamin brand you can find. But again, I am not a doctor!

Down Syndrome Or Up? By Val Haderlie

In 1866, when John Langdon Down came to a point in his research on the chromosomal disorder Trisomy 21 where he could describe the definitive characteristics of this genetic disorder, he simply named it "Down syndrome" after himself. This naming probably had much less to do with the doctor's ego than it had to do with quickly giving his findings a classification and moving forward with his research work.

Until the designation, Down syndrome, was made late in the eighteenth century, people who had the easily recognized physical characteristics of the anomaly were known, among other less appealing labels, as "mongoloid" because of their distinctly oriental facial features. As late as 1972, World Book Encyclopedia had entries for "mongolism" and "mongoloid" but no mention of Dr. Down or of Down syndrome.

And until just a few decades ago, individuals with Trisomy 21 were generally institutionalized for life. Identified babies and young children were taken from parents to become ward of the state. Doctors would calmly advise the devastated parents, "Forget you have this child. Go on with your life. Have another baby. Enjoy your family." Hearts were broken, human potential was wasted, and hopes were crushed and, over the years, parents and families began to rebel. They raised their cry, "No! This is my baby, the child of my heart. You have no right to put this baby away!" They declared, "We will raise this child as part of our family. Our child deserves and will have a life with us, not the State."

Happily, great strides have been made in offering people with Trisomy 21 lives of dignity and productivity. In today's age of enlightenment, much is being done to recognize the capabilities of citizens with Down syndrome. Inclusive education has allowed most people with Down syndrome to function, learn, and adapt in an environment populated mostly by the severely normal, the mainstream. Such an education offers opportunities to behave in socially acceptable ways and to participate in what peers are doing. This situation in itself is a huge step for those who are challenged with mental disability.

The term Down syndrome has had interesting ramifications which include interpreting it as a sad, hopeless and reticent emotional state combined with a condition of mental disability. Nothing could be further from the truth, as those of you who have close association with individuals with Down syndrome can attest. Admittedly, various ranges of mental disability are a given, but in general, those with Down syndrome are happy, congenial, sociable people.

Although debilitating physical challenges may accompany this syndrome, including heart defects and respiratory weakness, a high percentage of individuals with Down syndrome have the health and mobility to live active and emotionally rewarding lives. With early interventions, many speak intelligibly, perform employment tasks reliably, and interact delightfully in social settings. It's too bad that back in 1866, the researcher wasn't named John Langdon Up, but that's okay. It's not too late to change the name. Hooray for Up syndrome!

What Are the Types of Down Syndrome Screening? By Mike Selvon

There are two types of prenatal Down syndrome screening tests. Screening tests can let you know if your baby does not have this chromosomal disorder, while later diagnostic tests can confirm that the fetus does, in fact, have Down syndrome. Generally screenings are done around 11 weeks and later tests, between the 15th and 20th week of gestation, are performed if there is reason to believe the baby may be at risk.

Screening tests are very non-invasive and relatively painless. These Down syndrome screening procedures are primarily done to let parents know whether or not they want further testing done. One screening test for Down syndrome is called Nuchal translucency testing, which is performed between 11 and 14 weeks of pregnancy.

Using ultrasound, doctors can measure the space in the folds of tissue behind a baby's neck where excess fluid typically accumulates for babies with Down syndrome. This procedure accurately predicts Down syndrome 80% of the time. Additionally, a blood test called "the triple screen" or "multiple marker test" is also performed at the 15-20 week mark. Doctors will check the blood for alpha fetoprotein plus, plasma protein-A and the hormone chorionic gondatropin.

The second type of Down syndrome diagnostic tests are about 99% accurate in detecting signs of this chromosomal disorder. However, these procedures are more invasive and sometimes result in a miscarriage or other complications. Typically, doctors only perform these tests on women over 35, if genealogy warrants it or if they've tested positive in the initial screening. Amniocentesis, performed from 16 to 20 weeks, uses a needle to remove a small amount of amniotic fluid from the womb.

While it's an out-patient treatment, women may experience cramping, bleeding and infection, not to mention that 2-3% of patients lose their baby. As a result, amniocentesis is not recommended before the 14th week of gestation. Chorionic villus sampling and percutaneous umbilical blood sampling are other alternatives.

With chorionic villus sampling, a small sample of placenta is removed through a needle inserted into the abdomen. This Down syndrome screening can be done between the 10-12th weeks of gestation. Rate of miscarriage following the procedure is 3-5% and the use of CVS before the 10th week of pregnancy resulted in babies with missing or shortened fingers or toes. At the 20-week mark, percutaneous umbilical blood sampling (PUBS) can test for Down syndrome. A small sample of blood is removed from the umbilical cord and the risks are comparable to amniocentesis.

The Down Syndrome By Francesco Zinzaro Platinum

The clinical features of Down syndrome had been described over a century ago. Even though the underlying cause-an extra copy of chromosome 21-has been recognized for more than four decades, the almost total DNA sequence of chromosome 21-some 33,546,361 base pairs-was determined only 4 many years ago, and also the romantic relationship of genotype to phenotype is just beginning to become understood.

Down syndrome is broadly representative of aneuploid problems, or those that are caused by a deviation in the normal chromosome complement (euploidy). Chromosome 21, which contains just a little less than 2% of the total genome, is among the acrocentric autosomes (the others are 13, 14, 15, and 22), which means one in which almost all of the DNA lies on one side of the centromere. Generally, aneuploidy might include part or all of an autosome or sex chromosome.

Most individuals with Lower syndrome have 47 chromosomes (ie, a single additional chromosome 21, or trisomy 21) and are born to parents with regular karyotypes. This kind of aneuploidy is generally brought on by non-disjunction throughout meiotic segregation, which signifies failure of two homologous chromosomes to separate (disjoin) from each other at anaphase.

In contrast, aneuploid problems that affect component of an autosome or sex chromosome should at some point involve DNA breakage and reunion. DNA rearrangements are an infrequent but important trigger of Lower syndrome and are generally evident as a karyotype with 46 chromosomes by which one chromosome 21 is fused via its centromere to an additional acrocentric chromosome.

This abnormal chromosome is described like a robertsonian translocation and can occasionally be inherited from a carrier parent. Thus, Down syndrome may be brought on by a range of different karyotypic abnormalities, which have in common a 50% improve in gene dosage for almost all from the genes on chromosome 21.

Down syndrome occurs approximately as soon as in each and every 700 reside births and accounts for around one third of all cases of mental retardation. The likelihood of conceiving a child with Lower syndrome is related exponentially to growing maternal age group. However, screening programs detect most lower syndrome pregnancies in pregnant ladies older than 35 years.

This truth, combined using the inverse relationship of maternal age group to overall birth rate, means that most children with Down syndrome are now born to women younger than 35 many years. The condition is usually suspected within the perinatal time period in the presence of characteristic facial and dysmorphic functions this kind of as brachycephaly, epicanthal folds, small ears, transverse palmar creases, and hypotonia.

Approximately 50% of affected kids have congenital heart defects that arrive to medical attention within the immediate perinatal period because of cardiorespiratory difficulties. Strong suspicion from the situation on clinical grounds is generally confirmed by karyotyping inside 2-3 days.

An excellent numerous minor and main abnormalities happen with increased frequency in Down syndrome, yet two impacted individuals hardly ever have the exact same set of abnormalities, and several single abnormalities can be observed in unaffected individuals.

For example, the occurrence of the transverse palmar crease in Down syndrome is about 50%, ten times that within the common populace, however most people in whom transverse palmar creases are the only unusual feature do not have Lower syndrome or any other genetic illness.

The organic history of Lower syndrome in childhood is characterized primarily by developmental delay, growth retardation, and immunodeficiency. Developmental delay is generally apparent by 3-6 months of age as failure to attain age-appropriate developmental milestones and affects all aspects of motor and cognitive function.

The mean IQ is in between 30 and 70 and declines with increasing age. Nevertheless, there is a considerable range in the degree of psychological retardation in adults with Down syndrome, and many impacted people can reside semi-independently.

Generally, cognitive skills are a lot more restricted than affective overall performance, and only a minority of affected people are severely impaired. Retardation of linear growth is moderate, and most adults with Lower syndrome have statures 2-3 regular deviations beneath that from the general population.

In contrast, weight development in Lower syndrome exhibits a mild proportionate improve compared with that from the general population, and most adults with Down syndrome are overweight. Although increased susceptibility to infections is a common clinical function at all ages, the nature of the underlying abnormality isn't nicely understood, and laboratory abnormalities can be detected in both humoral and cellular immunity.

Among the most prevalent and dramatic medical functions of Down syndrome-premature onset of Alzheimer's disease-is not evident until adulthood. Even though frank dementia isn't clinically detectable in all adults with Lower syndrome, the occurrence of standard neuropathologic changes-senile plaques and neurofibrillary tangles-is nearly 100% by age 35 years.

The major causes of morbidity in Down syndrome are congenital center illness, infections, and leukemia. Life expectancy depends to a large extent on the presence of congenital heart illness; survival to ages 10 and 30 many years is around 60% and 50%, respectively, for people with congenital heart illness and approximately 85% and 80%, respectively, for people without congenital heart disease.

The advent of molecular markers for various portions of chromosome 21 supplied considerable information about when and how the extra chromosomal material arises in Down syndrome; and also the Human Genome Project has provided a list from the around 230 genes discovered on chromosome 21.

In contrast, a lot much less is recognized about why elevated gene dosage for chromosome 21 ought to produce the medical features of Down syndrome. For trisomy 21 (47,XX+21 or 47,XY+21), cytogenetic or molecular markers that distinguish between the maternal and paternal copies of chromosome 21 can be used to figure out whether the egg or the sperm contributed the extra copy of chromosome 21.

You will find no obvious medical differences between these two kinds of trisomy 21 individuals, which suggests that gametic imprinting doesn't perform a significant part within the pathogenesis of Lower syndrome. If each copies of chromosome 21 carried by each parent could be distinguished, it is usually feasible to figure out regardless of whether the nondisjunction event primary to an irregular gamete occurred during anaphase of meiosis I or meiosis II.

Studies this kind of as these show that approximately 75% of instances of trisomy 21 are caused by an additional maternal chromosome, that approximately 75% from the nondisjunction events (each maternal and paternal) occur in meiosis I, and that both maternal and paternal nondisjunction events improve with advanced maternal age group.

A number of theories have been proposed to clarify why the incidence of Lower syndrome increases with sophisticated maternal age group. Most germ cell improvement in females is completed before birth; oocytes arrest at prophase of meiosis I (the dictyotene stage) during the second trimester of gestation.

One proposal suggests that biochemical abnormalities that have an effect on the capability of paired chromosomes to disjoin usually accumulate in these cells over time and that, without a renewable source of fresh eggs, the proportion of eggs undergoing nondisjunction raises with maternal age group.

However, this hypothesis does not explain why the romantic relationship in between the occurrence of trisomy 21 and sophisticated maternal age group holds for paternal as well as maternal nondisjunction occasions.

An additional hypothesis proposes that structural, hormonal, and immunologic changes that occur within the uterus with sophisticated age produce an environment less capable to reject a developmentally irregular embryo. Therefore, an older uterus will be a lot more most likely to assistance a trisomy 21 conceptus to term regardless of which parent contributed the additional chromosome.

This hypothesis can explain why paternal nondisjunction errors improve with advanced maternal age. Nevertheless, it doesn't explain why the occurrence of Down syndrome resulting from chromosomal rearrangements (see later discussion) does not increase with maternal age group.

These along with other hypotheses are not mutually exclusive, and it's feasible that a mixture of elements is accountable for the relationship in between the occurrence of trisomy 21 and sophisticated maternal age. A number of environmental and genetic elements have been considered as possible causes of Lower syndrome, including exposure to caffeine, alcohol, tobacco, radiation, and the likelihood of carrying a single or a lot more genes that would predispose to nondisjunction.

Although it is hard to exclude all of these possibilities from consideration as minor factors, there is no evidence that any of those factors play a role in Down syndrome. The recurrence risk for trisomy 21 isn't altered significantly by getting had previous impacted kids.

Nevertheless, approximately 5% of Lower syndrome karyotypes have 46 instead of 47 chromosomes consequently of robertsonian translocations that usually include chromosomes 14 or 22. As described, this kind of abnormality is not associated with elevated maternal age group; nevertheless, in about 30% of such individuals, cytogenetic evaluation of the parents reveals a so-called balanced rearrangement this kind of as 45,XX,+t(14q;21q).

Because the robertsonian translocation chromosome can pair with each of its component single acrocentric chromosomes at meiosis, the likelihood of segregation primary to unbalanced gametes is significant, and also the recurrence risk to the parent with the irregular karyotype is a lot higher than for trisomy 21.

Around 1% of Down syndrome karyotypes display mosaicism by which some cells are normal and some irregular. Somatic mosaicism for trisomy 21 or other aneuploid conditions might initially arise either pre- or postzygotically, corresponding to nondisjunction in meiosis or mitosis, respectively.

In the former situation (one in which a zygote is conceived from an aneuploid gamete), the additional chromosome is then presumably lost mitotically in a clone of cells during early embryogenesis. The variety of phenotypes observed in mosaic trisomy 21 is excellent, ranging from slight psychological retardation with subtle dysmorphic functions to "typical" Down syndrome, and doesn't correlate with the proportion of irregular cells detected in lymphocytes or fibroblasts. Nonetheless, on typical, psychological retardation in mosaic trisomy 21 is generally milder than in nonmosaic trisomy 21.

Do You Know What Causes Down Syndrome? By Mike Selvon

Down syndrome children are a lot of work. Parents will need a team of doctors, including a cardiologist, a gastroenterologist, a pediatrician and other specialists, like speech therapists. Babies with Down syndrome may have trouble learning to roll over, sit up, feed, walk or talk. However, the temperament of these children is often extremely loving, loyal and gentle, which is why some doctors say raising a child with Down syndrome can be a rewarding experience. What causes Down syndrome boils down to genetics, although there is no way to prevent it.

An error in cell division is what causes this chromosomal disorder, experts say. Typically, human cells have 46 chromosomes; half from the sperm and half from the egg. Occasionally, extra genetic material builds up on the 21st chromosome when cells divide improperly and chromosome 21 becomes a trio, rather than a standard pair. In fact, another name of Down syndrome is "Trisomy 21." The triple chromosome will then continue to replicate improperly in each growing cell.

Doctors found that what causes Down syndrome environmentally may be the parents' age. For example, a 25-year-old mother has a 1/3,000 chance of having a baby with Down syndrome. By age 35, her risk will have increased to 1/365 and by 45, it will be a 1/30 chance of having a baby with the genetic condition! The latest Down syndrome research suggests that older fathers are now responsible for the 50% rise in risk, when the mother is also over 40.

Even though the odds get worse as the parents age, 80% of these babies are born to women who are 35 or younger. However, that statistic can also be explained because younger women are having many more babies. Younger mothers who smoke and have a meiotic II error or who smoke and take oral contraceptives are at increased risk for having a Down child as well.

During pregnancy, there are several screening tests to examine what causes Down syndrome. Some people get blood tests like the quad screen, which reveals chromosomal disorders between the eleventh and fourteenth weeks of pregnancy. Doctors look for plasma protein-A and the human chorionic gonadotropin hormone.

This test is about 87% effective in making a Down syndrome diagnosis. Ultrasound is another method to check for abnormalities. While these tests may give parents peace of mind, they may also set off a false alarm. Even though 1/20 women test positive, most will go on to deliver healthy babies anyway.

Everything About Down Syndrome By George Key

The people who suffer from Down syndrome have average to low cognitive abilities and the chances of Down syndrome are 1 to 1000 births. Also this ratio greatly depends upon the age of the mother and many other factors. many of the symptoms of down syndrome may also be found in normal people such as poor muscle growth, ear infections, obstructive sleep, thyroid dysfunctions etc. It is advised that as soon as this syndrome is detected in children they should be treated in a conducive family environment and vocational training should be provided to them for their development. All of the symptoms of Down syndrome can not be overcome but with proper care and education, the life of the people affected from syndrome can be greatly improved.

Characteristics of Down syndrome:

People suffering from Down syndrome may have some of the following physical characteristics:

o Oblique eye fissures

o Muscle hypotonia

o Flat nasal bridge

o Single plamar fold

o Short neck

o White spots on the iris

o Congenital heart defects

o Single Flexion furrow of the fifth finger

o Higher number of ilnar loop dermatoglyphs

Some mental characteristics include:

o Mental retardation

o Low IQ due to above factor

These are just some of symptoms of the Down syndrome. Their are many other symptoms of this dreadful disorder.

Health of people:

The people suffering from this syndrome can experience any organ or organ system failure at any time. This type of syndrome can result from many genetic disorders. This results in wide variety of symptoms and even wider variety of problems and complications in the individuals. Prior to birth it can be tested and found out that the individual which will develop will have Down syndrome while some symptoms are clearly visible after the birth like heart malfunctions others come to light in the later years.

A survey conducted in United States showed that the life acceptancy of such people is around 49 years up from 25 years in 1980.The life expectancy also depends on many factors like the social environment of the individual as well as the family environment. Fertility is drastically reduced with males suffering the worst. Only 3 instances of a male suffering from Down syndrome becoming a father have been recorded.

People who support such people advise that such people should be given special guidance as well as education as well as a home environment which is suitable and caring for them and then only thy develop their minds to live like a normal person. With special care and understanding the world can be made a better place to live in for individuals suffering from Down syndrome.

What Causes Down Syndrome? By Aaroah Sunil

What is Down's Syndrome

Down's syndrome is defined as a disease that comes about because of a genetic abnormality that negatively affects the mental capabilities and physical features of an affected person. Individuals with this condition quite often experience varying degrees of medical and physical issues. Some people with the disease are able to successfully lead moderately regular lives while others need persistent medical care. It affects 1 in 800 newborns and is said to be more common with older mothers. The disease cannot be prevented, however it can be discovered in utero, before the baby is born. There is still much controversy in relation to the ramifications of genetic testing for Down'ssyndrome. It has been observed that an estimated 90-93% of pregnancies with a Down's babies were aborted once this was identified through various forms of genetic testing methods.

The outlook for children with Down's syndrome has significantly improved in recent years. The regular life span for an individual with Down's syndrome was 25 years old in the 1980's it has now risen to 49 years of age in present times. People with the disease will usually be infertile especially males who are only partially fertile in extremely rare instances. Most children with Down's syndrome will also experience noticeably reduced cognitive abilities. However, with needed medical intervention, family support and vocational training the child with down syndrome can learn to overcome, to some extent, his or her disabilities.

What Causes Down's Syndrome

The disease as mentioned before is caused by a genetic irregularity. A normal person will have 46 chromosomes, 23 of which will be inherited from either parent. In an individual with Down's syndrome he or she will have an overall number of 47 chromosomes or essentially 1 more chromosome than is expected. This chromosomal abnormality manifests because of an extra copy of the 21st chromosome. The effect of the extra copy will vary among affected people.

The condition cannot be prevented and is said to be a randomly occurring event. However women over the age of 35 are at an increased risk of conceiving a child with Down syndrome. The risk for different age groups are listed below:

o Women who are 25 years of age will typically have a 1in 1,250 chance of having a Down's baby.

o Women who are 30 years of age will normally have. 1 in 1000 chance of having a Down's baby.

o Women who are 35 years of age will normally have 1in 400 chance of having a Down's baby.

o Women who are 40 years of age will typically have 1 in 100 chance of having a Down's baby.

o Women who are 45 years of age will normally have. 1 in 30 chance of having a Down's baby.

The odds of conceiving a child with Down's Syndrome may also be associated with a familial genetic irregularity. A person who has a balanced translocation will not show any signs of down syndrome but will have an elveated risk of conceiving a child with translocation Down syndrome. The estimated risk is 1 in 5 for the female carrier and 1 in 50 for a male carrier. In some cases where there is no unattached copy of chromosome 21 the carrier's offspring will all have Down's Syndrome. The affected parent is therefore said to be a translocation carrier. This sort of Down's syndrome is said to occur in 2-3% of all Down's syndrome cases.

Down Syndrome By Kok Siong Chen

Down syndrome is a common genetic chromosomal syndrome among the population in the world. It is about 1 in 800 liveborns in the population with Down syndrome. This syndrome is starts to be described by a physician named John Langdon Down who published an article in 1866. He stated that there are some children with common characteristics but distinct from other children with mental retardation. He described this syndrome as "Mongoloids". He used this unfortunate name just because of those children looked like people from Mongolia. The "Mongoloids" was dropped from scientific use since 1960s to stop the ethic insult.

About 95% of all patients with Down syndrome have a 47, +21 karyotype. Among these cases there is a small group with familial translocation involving a chromosome 21 and another chromosome with balanced rearrangement. There are some very rare instances of direct transmission of the additional 21 from a Down syndrome mother or father to a Down syndrome child.

Down syndrome patient looks almost alike to each other. We can simply identify the Down syndrome patient by just looking to their physical outlook. However, a confident clinical diagnosis might be difficult early after birth, especially in prematures. Some of the useful diagnostic signs are brachycephaly (flat-head), small ears, Brushfield spots (brown spots on the periphery of the iris) and low iliac and acetabular index in pelvic radiographs. Congenital malformations are frequent in Down syndrome patients too. Thyroid dysfunction is also significantly associated with Down syndrome and might be the cause for developmental delay. Mentally retardation is the most common feature among the Down syndrome patients.

Generally, female menarche occurs at normal time and pregnancies are common among the Down syndrome patients. However, there is hypogenitalism and hypogonadism among the male patients. Therefore, the male with Down syndrome usually is infertile.

In conclusion, Down syndrome patients need to be taken care as there are various specific problems throughout their life. I will write more about the guideline for optimal medical care on these Down syndrome patients later.

What is Down Syndrome? By Jane Orville

Every year, one child in every 800 to 1,000 births will be born with a condition known as Down syndrome. Down syndrome is a disorder in which the child has extra genetic material. This extra genetic material causes the baby to develop differently in the womb. This abnormal development occurs during the early stages of cell division, soon after conception.

There is no known reason for Down syndrome or a cure for it.

The disorder came by its name when an English physician, John Langdon Down, published a description of the characteristics of a person with the condition in 1886. Since Dr. Down was the first person to give the syndrome a name, the disorder is known as Down syndrome.

The Common Forms of Downs

There are three distinct forms of Down syndrome. The most common form is Trisomy 21. This is when a child has an extra chromosome 21.

Instead of having 46 chromosomes in each cell (23 from the father and 23 from the mother), he has 47. Ninety-five percent of children born with Down syndrome have Trisomy 21.

Translocation is another form of Down syndrome and makes up 3 to 4% of the population of people with the disorder. Translocation occurs when part of chromosome 21 breaks off and attaches to another chromosome, changing the genetic makeup. In this form of Down syndrome, each cell has the normal 46 chromosomes, but there is extra genetic material from the broken off chromosome.

The third and final form is called Mosaicism, and is the rarest form of Down syndrome, occurring in only 2% of all cases. Mosaicism happens when some of the cells in the forming embryo have 46 chromosomes, and some have 47. Thus, the alternating pattern gives it the name Mosaicism.

People with Mosaicism may not be as affected with the physical and/or developmentally delayed characteristics of those born with the other two forms of Down syndrome.

Common Physical Traits

Babies with Down syndrome are usually diagnosed at birth or shortly thereafter. Because Down syndrome affects a child physically, there will be certain features that an alert doctor or nurse will pick up on. Most children with the syndrome will have some or all of these traits.

Among the most common physical characteristics are:

o Low muscle tone

o Small nose and flat nasal bridge

o An upward slant to the eyes (almond shaped)

o Small skin folds on the inner corner of the eyes

o Tongue large for size of child's mouth

o Small, sometimes abnormally shaped ears

o A single crease across the center of the palm

o Fifth finger, the pinky, has only one crease instead of two

o Larger than normal space between the large and second toe

o Joints are hyper flexible, able to extend greater than average

These physical traits are characteristic of a baby with Down syndrome, but in order to determine if a child does indeed have the disorder, a chromosome analysis will need to be performed.

This is done by taking blood from your baby and the analysis will be done in a laboratory. Your doctor will notify you of the results.

The Down Syndrome By Francesco Zinzaro Platinum

The clinical features of Down syndrome had been described over a century ago. Even though the underlying cause-an extra copy of chromosome 21-has been recognized for more than four decades, the almost total DNA sequence of chromosome 21-some 33,546,361 base pairs-was determined only 4 many years ago, and also the romantic relationship of genotype to phenotype is just beginning to become understood.

Down syndrome is broadly representative of aneuploid problems, or those that are caused by a deviation in the normal chromosome complement (euploidy). Chromosome 21, which contains just a little less than 2% of the total genome, is among the acrocentric autosomes (the others are 13, 14, 15, and 22), which means one in which almost all of the DNA lies on one side of the centromere. Generally, aneuploidy might include part or all of an autosome or sex chromosome.

Most individuals with Lower syndrome have 47 chromosomes (ie, a single additional chromosome 21, or trisomy 21) and are born to parents with regular karyotypes. This kind of aneuploidy is generally brought on by non-disjunction throughout meiotic segregation, which signifies failure of two homologous chromosomes to separate (disjoin) from each other at anaphase.

In contrast, aneuploid problems that affect component of an autosome or sex chromosome should at some point involve DNA breakage and reunion. DNA rearrangements are an infrequent but important trigger of Lower syndrome and are generally evident as a karyotype with 46 chromosomes by which one chromosome 21 is fused via its centromere to an additional acrocentric chromosome.

This abnormal chromosome is described like a robertsonian translocation and can occasionally be inherited from a carrier parent. Thus, Down syndrome may be brought on by a range of different karyotypic abnormalities, which have in common a 50% improve in gene dosage for almost all from the genes on chromosome 21.

Down syndrome occurs approximately as soon as in each and every 700 reside births and accounts for around one third of all cases of mental retardation. The likelihood of conceiving a child with Lower syndrome is related exponentially to growing maternal age group. However, screening programs detect most lower syndrome pregnancies in pregnant ladies older than 35 years.

This truth, combined using the inverse relationship of maternal age group to overall birth rate, means that most children with Down syndrome are now born to women younger than 35 many years. The condition is usually suspected within the perinatal time period in the presence of characteristic facial and dysmorphic functions this kind of as brachycephaly, epicanthal folds, small ears, transverse palmar creases, and hypotonia.

Approximately 50% of affected kids have congenital heart defects that arrive to medical attention within the immediate perinatal period because of cardiorespiratory difficulties. Strong suspicion from the situation on clinical grounds is generally confirmed by karyotyping inside 2-3 days.

An excellent numerous minor and main abnormalities happen with increased frequency in Down syndrome, yet two impacted individuals hardly ever have the exact same set of abnormalities, and several single abnormalities can be observed in unaffected individuals.

For example, the occurrence of the transverse palmar crease in Down syndrome is about 50%, ten times that within the common populace, however most people in whom transverse palmar creases are the only unusual feature do not have Lower syndrome or any other genetic illness.

The organic history of Lower syndrome in childhood is characterized primarily by developmental delay, growth retardation, and immunodeficiency. Developmental delay is generally apparent by 3-6 months of age as failure to attain age-appropriate developmental milestones and affects all aspects of motor and cognitive function.

The mean IQ is in between 30 and 70 and declines with increasing age. Nevertheless, there is a considerable range in the degree of psychological retardation in adults with Down syndrome, and many impacted people can reside semi-independently.

Generally, cognitive skills are a lot more restricted than affective overall performance, and only a minority of affected people are severely impaired. Retardation of linear growth is moderate, and most adults with Lower syndrome have statures 2-3 regular deviations beneath that from the general population.

In contrast, weight development in Lower syndrome exhibits a mild proportionate improve compared with that from the general population, and most adults with Down syndrome are overweight. Although increased susceptibility to infections is a common clinical function at all ages, the nature of the underlying abnormality isn't nicely understood, and laboratory abnormalities can be detected in both humoral and cellular immunity.

Among the most prevalent and dramatic medical functions of Down syndrome-premature onset of Alzheimer's disease-is not evident until adulthood. Even though frank dementia isn't clinically detectable in all adults with Lower syndrome, the occurrence of standard neuropathologic changes-senile plaques and neurofibrillary tangles-is nearly 100% by age 35 years.

The major causes of morbidity in Down syndrome are congenital center illness, infections, and leukemia. Life expectancy depends to a large extent on the presence of congenital heart illness; survival to ages 10 and 30 many years is around 60% and 50%, respectively, for people with congenital heart illness and approximately 85% and 80%, respectively, for people without congenital heart disease.

The advent of molecular markers for various portions of chromosome 21 supplied considerable information about when and how the extra chromosomal material arises in Down syndrome; and also the Human Genome Project has provided a list from the around 230 genes discovered on chromosome 21.

In contrast, a lot much less is recognized about why elevated gene dosage for chromosome 21 ought to produce the medical features of Down syndrome. For trisomy 21 (47,XX+21 or 47,XY+21), cytogenetic or molecular markers that distinguish between the maternal and paternal copies of chromosome 21 can be used to figure out whether the egg or the sperm contributed the extra copy of chromosome 21.

You will find no obvious medical differences between these two kinds of trisomy 21 individuals, which suggests that gametic imprinting doesn't perform a significant part within the pathogenesis of Lower syndrome. If each copies of chromosome 21 carried by each parent could be distinguished, it is usually feasible to figure out regardless of whether the nondisjunction event primary to an irregular gamete occurred during anaphase of meiosis I or meiosis II.

Studies this kind of as these show that approximately 75% of instances of trisomy 21 are caused by an additional maternal chromosome, that approximately 75% from the nondisjunction events (each maternal and paternal) occur in meiosis I, and that both maternal and paternal nondisjunction events improve with advanced maternal age group.

A number of theories have been proposed to clarify why the incidence of Lower syndrome increases with sophisticated maternal age group. Most germ cell improvement in females is completed before birth; oocytes arrest at prophase of meiosis I (the dictyotene stage) during the second trimester of gestation.

One proposal suggests that biochemical abnormalities that have an effect on the capability of paired chromosomes to disjoin usually accumulate in these cells over time and that, without a renewable source of fresh eggs, the proportion of eggs undergoing nondisjunction raises with maternal age group.

However, this hypothesis does not explain why the romantic relationship in between the occurrence of trisomy 21 and sophisticated maternal age group holds for paternal as well as maternal nondisjunction occasions.

An additional hypothesis proposes that structural, hormonal, and immunologic changes that occur within the uterus with sophisticated age produce an environment less capable to reject a developmentally irregular embryo. Therefore, an older uterus will be a lot more most likely to assistance a trisomy 21 conceptus to term regardless of which parent contributed the additional chromosome.

This hypothesis can explain why paternal nondisjunction errors improve with advanced maternal age. Nevertheless, it doesn't explain why the occurrence of Down syndrome resulting from chromosomal rearrangements (see later discussion) does not increase with maternal age group.

These along with other hypotheses are not mutually exclusive, and it's feasible that a mixture of elements is accountable for the relationship in between the occurrence of trisomy 21 and sophisticated maternal age. A number of environmental and genetic elements have been considered as possible causes of Lower syndrome, including exposure to caffeine, alcohol, tobacco, radiation, and the likelihood of carrying a single or a lot more genes that would predispose to nondisjunction.

Although it is hard to exclude all of these possibilities from consideration as minor factors, there is no evidence that any of those factors play a role in Down syndrome. The recurrence risk for trisomy 21 isn't altered significantly by getting had previous impacted kids.

Nevertheless, approximately 5% of Lower syndrome karyotypes have 46 instead of 47 chromosomes consequently of robertsonian translocations that usually include chromosomes 14 or 22. As described, this kind of abnormality is not associated with elevated maternal age group; nevertheless, in about 30% of such individuals, cytogenetic evaluation of the parents reveals a so-called balanced rearrangement this kind of as 45,XX,+t(14q;21q).

Because the robertsonian translocation chromosome can pair with each of its component single acrocentric chromosomes at meiosis, the likelihood of segregation primary to unbalanced gametes is significant, and also the recurrence risk to the parent with the irregular karyotype is a lot higher than for trisomy 21.

Around 1% of Down syndrome karyotypes display mosaicism by which some cells are normal and some irregular. Somatic mosaicism for trisomy 21 or other aneuploid conditions might initially arise either pre- or postzygotically, corresponding to nondisjunction in meiosis or mitosis, respectively.

In the former situation (one in which a zygote is conceived from an aneuploid gamete), the additional chromosome is then presumably lost mitotically in a clone of cells during early embryogenesis. The variety of phenotypes observed in mosaic trisomy 21 is excellent, ranging from slight psychological retardation with subtle dysmorphic functions to "typical" Down syndrome, and doesn't correlate with the proportion of irregular cells detected in lymphocytes or fibroblasts. Nonetheless, on typical, psychological retardation in mosaic trisomy 21 is generally milder than in nonmosaic trisomy 21.

Who Has Down Syndrome Babies? by: Jane Orville

Most people associate having a child with Down syndrome with older women. While it is true that women over 35 do have an increased risk of having a child with Down syndrome, 80% of these children are born to those women under age thirty-five.

In the United States, approximately 5,000 babies with Down syndrome are born every year. A woman’s chance of having another baby with Down syndrome is approximately 1 in 100.

Prenatal Screening for Down Syndrome

Over the last 10 years, new technology has improved the methods of detection of Down syndrome. While there are ways to diagnose Down syndrome by obtaining fetal tissue samples by amniocentesis or chorionic villus sampling, it would not be appropriate to examine every pregnancy this way. Besides greatly increasing the cost of medical care, these methods do carry a slight amount of risk to the fetus.

So screening tests have been developed to try to identify those pregnancies at "high risk." These pregnancies are then candidates for further diagnostic testing.

Screening Vs Diagnostic Test

What is the difference between a screening test and a diagnostic test? In diagnostic tests, a positive result very likely means the patient has the disease or condition of concern. In screening tests, the goal is to estimate the risk of the patient having the disease or condition.

Diagnostic tests tend to be more expensive and require an elaborate procedure; screening tests are quick and easy to do. However, screening tests have more chances of being wrong: there are "false-positives" (test states the patient has the condition when the patient really doesn't) and "false-negatives" (patient has the condition but the test states he/she doesn't).

Maternal Serum Screening

The mother's blood is checked for three items: alpha-fetoprotein (AFP), unconjugated estriol (uE3) and human chorionic gonadotropin (hCG). These three are independent measurements, and when taken along with the maternal age (discussed below), can calculate the risk of having a baby with Down syndrome.

A very important consideration in the screening test is the age of the fetus (gestational age). The correct analysis of the different components depends on knowing the gestational age precisely. The best way to determine that is by ultrasound.

Test results are sometimes reported to doctors as "Multiples of the Median (MoM)." The "average" value is therefore called 1.0 MoM. Down syndrome pregnancies have lower levels of AFP and estriol, so their levels would be less than 1.0 MOM.

hCG in a Down syndrome pregnancy would be greater than 1.0 MoM.

Finally, the calculated risk is used to modify the risk already statistically calculated based on the mother's age. We already know that as the mother's age advances, the risk of having a baby with Down syndrome increases.

For example: Let's say the test results come back in the typical range for a pregnancy not associated with Down syndrome (that would be 1.0 MoM for all components). This result reduces the woman's risk of having a child with Down syndrome four-fold.