Down Syndrome in Children
Down syndrome is one of the most common and easily recognized genetic disorders. It is caused by abnormal cell division that involves the 21st chromosome pair of the 23 pairs of chromosome found in all normal human cells. There are three types of these abnormalities, which are non-disjunction, translocation, and mosaicism. Ninety five percent of children born with Down syndrome are a non-disjunction type which is three rather than two chromosome 21s. About three to four percent of cases are because of translocation which is chromosome 21 detaches and attaches to another chromosome. Mosaicism accounts for only one to two percent of births, which is an abnormal cell division with the normal 46 chromosomes
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Its very important to know that some screening test may slightly increase the chance of a miscarriage. Tests in utero for identifying Down syndrome include amniocentesis, which is a needle inserted into the uterus and a sample of the amniotic fluid surrounding the fetus is taken out. Usually used within 14-16 week of pregnancy. This test is 99% accurate, but carries a 0.5 percent chance of miscarriage. Chorionic villus sampling (C.V.S.) is used by taking cells from the placenta through the mother's abdominal wall or cervix. Performed between tenth and twelfth week of pregnancy, this test is 98 percent accurate and carries a risk of limb deformities and a one to two percent chance of a miscarriage. Karyotyping can be used through the process in which a picture of chromosomal patterns is prepared (Genetic Disorders.p5). An ultrasound can identify any traits a fetus has such as shortened thighbones or gastrointestinal blockage that can be associated with Down syndrome, but not as accurate to be used as a substitute for C.V.S. or amniocentesis in detecting Down syndrome.
Before the 1970's Down syndrome wasn't diagnosed until birth or even later, but due to such early diagnosing and screening this has posed a major dilemma for families and physicians. It allows parents to decide whether or not the pregnancy should be terminated (exceptional child book p176).
The physical description of a
It's hard to believe a random error in cell division known as nondisjunction can be the reason for so many birth defects. This one mistake is the cause of 1 in 691 babies being born with what is known as Down Syndrome. In every cell in the human body, there is a nucleus. Typically there are twenty three chromosomes in each nucleus. Down Syndrome occurs when there is extra full or partial copy of chromosome 21. Down Syndrome is a chromosomal condition that causes low muscle tone, small stature, and a single deep crease across the center of the palm. Although, each person with Down Syndrome is a unique individual and may have these characteristics to different degrees.
Babies can be screened for Down syndrome as part of prenatal care; however, these screenings don’t tell you if the baby has Down syndrome, it can only tell you how likely the baby is to have it. This first test is called the first trimester combined test. This includes blood tests and an ultrasound on the baby. Based on these two tests and age a doctor can try to estimate the likelihood of a baby having Down syndrome. If results come back positive and people think their kids has a great chance of having this genetic disorder they can try to have a few more tests done. Once the baby is born they first see if the baby has an visual symptoms. Appearance is a big key to knowing if a baby has Down syndrome right away when it is born. However, at times babies can have appearances that resemble Down syndrome even if they don’t have it so a test is done called a chromosomal karyotype which analyzes the child’s chromosomes. Once diagnosed a child should start treatment as soon as possible if they want to see more positive effects of the treatments. Usually doctors can refer patients to special early intervention programs in the area. These programs specialize in helping the diagnosed kids with developing different skills like: social, language and motor skills. Most kids will end up having a team of experts on their side. This would be a
There are three ways that a mother can be tested during pregnancy to see if their child will have Down syndrome. One is amniocentesis, which is the removal and analysis of a small sample of fetal cells from the amniotic fluid. Amniocentesis can not be done until the 14-18th week of pregnancy and with this process there is a lower risk of miscarriage than with the other two processes. Another process is chorionic villus sampling (CVS), which is the extraction of a tiny amount of fetal tissue at 9 to 11 weeks of pregnancy. The tissue is then tested for the presence of extra material from chromosome 21. Chorionic villus sampling has a 1-2% chance of the mother having a miscarriage. The last process is percutaneous umbilical blood sampling (PUBS), which is the most accurate method used to confirm the results of CVS or amniocentesis. During PUBS the tissue is tested for the presence of extra material from chromosome 21. PUBS cannot be done until the 18-22nd week and it carries a high risk of the mother having a miscarriage.
In the past, Down syndrome had been considered one of the most devastating disabilities. There were people who believed that it this disability was a death sentence, and how aborting these children was actually a service. They believed that life would be so horrible for someone with down syndrome that it’s best to terminate the pregnancy. This condition can be seen in utero because it is a genetic disorder, and there is a mutation within the genetic code. This can be seen in-utero, and is one of the reasons people check on their child in the womb. There was nothing that could be done for these children, and that is why many believed that termination was the best option.
The etiology of Down syndrome is due to a genetic mutation within chromosome 21. There are three types of Down syndrome, which include Trisomy 21, Mosaic Down Syndrome, and Translocation Down Syndrome. Trisomy 21 occurs when there are three copies of chromosome 21 in each nucleus, instead of the usual two. This type of Down syndrome occurs 95% of the time. Mosaic Down Syndrome occurs 1% of the time and is characterized by some cells having three pairs of chromosome 21 and others having the normal two. This is caused by abnormal cell division after
Do you feel like your child is having trouble developing? Is your child having trouble learning to speak, read, or walk? If so, you may want to get a screening test and a diagnostic test to see if your child has down syndrome.
Down syndrome is a congenital disorder arising from a chromosome defect, the chromosome causing the problems is Chromosome 21. This disorder affects about 1 in 700 births in the United States. Currently there are about 400,000 Americans that have Down syndrome, with approximately 6,000 babies are born with Down syndrome each year. The disorder forms during fertilization or soon after fertilization. Fertilization occurs when the sperm binds to zona pellucida, then the sperm undergoes acrosome reaction which will lyses a hole in zona pellucida, and then the sperm and egg membrane fuse. Once the membranes fuse, the sperms genetic material gets released and gets combined with the egg’s chromosomes, thus resulting in a 46 chromosome fertilized egg.
mother could have a Down Syndrome baby even though there was never any sign of
Two of the main methods, or tests, used to tell whether a child has Down syndrome or not are a screening test and a diagnostic test. The screening test doesn’t give a for sure answer, but an educated guess, which is typically accurate. These screenings typically include a blood test, to measure the quantity of various substances in the mother’s blood, and an ultrasound, to be able to see if there are any noticeable physical features which are typical of a child with Down syndrome. The diagnostic test has two different procedures. There’s the chorionic villus sampling, CVS, and amniocentesis. Both of these tests are always accurate and can even distinguish which type of Down syndrome the child has if it has the disorder (Diagnosis). With these tests, there is a small chance of a miscarriage, but that typically isn’t an issue. If the tests aren’t taken into place before the child is born, the doctor can usually diagnose the child right after being born by relating its physical symptoms to the ones of Down syndrome. Once diagnosed with Down syndrome, the next step is treatment
Down syndrome is characterized as a chronic genetic chromosomal disorder which alters one’s cognitive growth, intellectual development, and physical characteristics. This extremely widespread condition is most prominently existent in human beings whose genetic makeup is composed of an additional copy of chromosome 21. Additionally, these human beings are known for acquiring 47 chromosomes rather than the conventional 46 chromosomes. This chromosomal abnormality is extremely common, yet highly spontaneous. To illustrate, the prevalence of Down Syndrome is exhibited as around
Fetal screening is among one of the most common procedures done to females to track the baby's health. During this common procedure a series of tests are done as well as questions for both the mother and father. In most cases, doctors often screen fetus’s because of the risk of Down Syndrome some might have. Those who are more prone to carrying genes or history of Down Syndrome should consider screening the child to better prepare the parents of the possible outcome they might have. Fetal Screening is complex by the relevance of the ultrasound and the evidence it can provide about the baby’s health which can foresee human diversity and discrimination.
Down syndrome is a genetic disorder also known as trisomy 21, that develops when there is an extra chromosome inside the cells of a person. Normally a person has 46 chromosomes so when a developing infant has an extra chromosome 21 they will have 47 chromosomes in a cell causing them to develop Down syndrome. Although you might think it is hereditary Down syndrome is not passed down from parent to baby nor do we know why it happens, it occurs at conception and there is no cure for it nor does it go away.
Down syndrome is commonly known by the public as a disease that causes physical and mental disabilities in people. Down syndrome is known by the scientific community as a genetic disorder of the twenty-first chromosome. As a result of this genetic disorder other systems of the body are also affected, this includes mental and physical disabilities. Down syndrome “is a lifelong condition… that happens before birth” (WebMD, 2015). According to the National Down Syndrome Society one in every 691 babies are born with the condition (NDSS, 2015). In order to understand this condition it is
. Down syndrome is not a disease that someone catches and is not caused by difficulties during the pregnancy, it is a genetic condition. This condition is caused by the presence of an extra chromosome in the body’s cells and causes a redundant amount of proteins to be formed. All cells of the body derive from a single cell formed by the fusion of a father’s sperm and a mother’s egg. Each cell carries a nucleus full of genetic material known as genes. These genes are inherited from both the mother and father. Each cell normally contains 46 pairs of chromosomes. 23 chromosomes come from one parent and 23 from the other, hence the 46 pairs. When it comes to children with down syndrome, one of the chromosomes does not separate properly and so the
Down syndrome was named after John Langdon Down, who was the first person to discover Down syndrome. In the earlier years it was called Mongolism, which is no longer used because it is offensive to the Mongolians. James N. Parker and Philip M. Parker state “Down syndrome is a chromosomal disorder caused by an error in cell division that results in the presence of an additional third chromosome 21 or ‘trisomy 21’” (10). There are different types of Down Syndrome according to the National Down Syndrome Society (NDSS), there is Trisomy 21, Mosaicism, and Translocation (What is Down syndrome?). There is no way to prevent having a baby with Down syndrome although chances increase as the woman gets older. The NDSS says, “A 35-year-old woman has about a 1 in 350 chance of conceiving a child with Down syndrome, and this chance increases gradually to 1 in 100 by age 40” (What is Down syndrome?). Although the risk is greater for older women, it is still possible to have a child with Down syndrome at a younger age.