Women aged 30—35 years or above might receive genetic screening during pregnancy. This is because the chance of having a child with Down syndrome increases as women age.
Screening is a cost-effective and less invasive way to determine whether more invasive diagnostic tests are needed. Diagnostic tests are more accurate for detecting Down syndrome. A healthcare professional will usually perform such tests inside the uterus. A healthcare professional can also diagnose Down syndrome after a baby is born by inspecting their physical characteristics, blood, and tissue.
There is no specific treatment for Down syndrome. People who have the condition will receive care for any health problems, as other people do. However, healthcare professionals may recommend additional health screening for issues common to the condition.
Early intervention can help a person maximize their potential and prepare them to take up an active role in the community. Physicians, special educators, speech therapists, occupational therapists, and physical therapists, as well as social workers, can all help. The National Institute for Child Health and Human Development urge all specialists to provide stimulation and encouragement.
Children with specific learning and development difficulties may be eligible for educational support, either in a mainstream or specialized school. In recent years, the tendency has been to attend mainstream schools, often with additional support to help them integrate and progress.
The most common form of Down syndrome is called trisomy This is a condition wherein people have 47 chromosomes in each cell instead of An error in cell division called nondisjunction causes trisomy This error leaves a sperm or egg cell with an extra copy of chromosome 21 before or at conception.
This variant accounts for 95 percent of Down syndrome cases. The remaining 5 percent of Down syndrome cases are due to conditions called mosaicism and translocation.
Mosaic Down syndrome occurs when some cells in the body are normal, while others have trisomy Robertsonian translocation occurs when part of chromosome 21 breaks off during cell division and attaches to another chromosome, usually chromosome The presence of this extra part of chromosome 21 causes some Down syndrome characteristics.
A person with a translocation does not have any special physical features, but they are more likely to have a child with an extra chromosome A person with Down syndrome can do many of the things that other people do. In nondisjunction, something goes wrong and both chromosomes from one pair go into one cell and no chromosomes for that pair go into the other cell. Most of the time, the error occurs at random during the formation of an egg or sperm.
To date, no behavioral activity of the parents or environmental factor is known to cause Down syndrome. After much research on these cell division errors, researchers know that: 2.
As the registry grows, families and researchers learn more about Down syndrome and identify similarities and differences in the symptoms and treatment of people with Down syndrome from around the world. The information collected helps guide future research and treatment. In the remaining cases, the error occurs after fertilization, as the embryo grows. Complete trisomy In this case, an error during the formation of the egg or the sperm results in either one having an extra chromosome.
So after the egg and sperm unite, the resulting cells will also have three copies of chromosome Most cases are sporadic — chance — events. However, in about one-third of cases, one parent is a carrier of a translocated chromosome. Once a woman has given birth to a baby with trisomy 21 nondisjunction or translocation, it is estimated that her chances of having another baby with trisomy 21 is 1 in up until age Genetic counseling can determine the origin of translocation.
There are two categories of tests for Down syndrome that can be performed before a baby is born: screening tests and diagnostic tests. Prenatal screens estimate the chance of the fetus having Down syndrome. These tests do not tell you for sure whether your fetus has Down syndrome; they only provide a probability. There is an extensive menu of prenatal screening tests now available for pregnant women. Most screening tests involve a blood test and an ultrasound sonogram. The blood tests or serum screening tests measure quantities of various substances in the blood of the mother.
New advanced prenatal screens are now able to detect chromosomal material from the fetus that is circulating in the maternal blood. These tests are not invasive like the diagnostic tests below , but they provide a high accuracy rate. Still, all of these screens will not definitively diagnose Down syndrome. Prenatal screening and diagnostic tests are now routinely offered to women of all ages. The diagnostic procedures available for prenatal diagnosis of Down syndrome are chorionic villus sampling CVS and amniocentesis.
Amniocentesis is usually performed in the second trimester between 15 and 20 weeks of gestation, CVS in the first trimester between 9 and 14 weeks.
Down syndrome is usually identified at birth by the presence of certain physical traits: low muscle tone, a single deep crease across the palm of the hand, a slightly flattened facial profile and an upward slant to the eyes.
Because these features may be present in babies without Down syndrome, a chromosomal analysis called a karyotype is done to confirm the diagnosis.
They photograph the chromosomes and then group them by size, number, and shape. By examining the karyotype, doctors can diagnose Down syndrome. Another genetic test called FISH can apply similar principles and confirm a diagnosis in a shorter amount of time. Individuals with Down syndrome are becoming increasingly integrated into society and community organizations, such as school, health care systems, work forces, and social and recreational activities.
Individuals with Down syndrome possess varying degrees of cognitive delays, from very mild to severe. Most people with Down syndrome have cognitive delays that are mild to moderate. Due to advances in medical technology, individuals with Down syndrome are living longer than ever before. In , children with Down syndrome were expected to survive to age nine.
With the discovery of antibiotics, the average survival age increased to 19 or More and more Americans are interacting with individuals with Down syndrome, increasing the need for widespread public education and acceptance. These downloadable versions of the Preferred Language Guide are available to print and distribute:.
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