Down+Syndrome


 * Down Syndrome**

Down Syndrome can be caused by mistakes in gamete cell division in Meiosis. Rarely is it caused by inheritance. However, the chromosomal defect can be passed down from the mother or father. It is one of the most common genetic birth defect and the most common cause of mental retardation. //Statistics// About 1 in 900 people are born with Down Syndrome Mothers 35 years and older are more likely to give birth to a child with Down Syndrome.

//Symptoms// • mental retardation • an upward slant to the eyes • decreased muscle tone • flattened facial profile - compressed nasal bridge • small mouth and nose • abnormal shape of ears • laxity around body joint • excessive space between first and second toe • a single, deep crease across the palm • enlarged tongue and a small mouth -symptoms vary-

//Causes// Down Syndrome is caused by an excess of genetic material, primarily in chromosome 21. 95% of the people with Down Syndrome have an extra chromosome 21. Only 4% of DS patients have an extra bit of chromosome 21 that is attached to another chromosome (usually chromosome 14). About 1% patients have a mixed pattern of cells in their bodies where some cell have normal amounts of genetic material and others have an extra chromosome 21. //Testing// Prenatal testing can be used to see if the fetus has DS. However, when a baby is born, you can often tell by their physical features if they have DS. A karyotype can be used to test for DS as well. //Treatment// There is no cure for DS. However, heart defects, hearing deficits, and development delays, which are common effects from DS, are treatable.

http://www.ygyh.org/ds