Down Syndrome 3
Down Syndrome Down Syndrome is a chromosomal disorder. It occurs in about 1 of every 800 births. People with Down syndrome may have mild to severe learning disabilities. Physical symptoms include a small skull, extra folds of skin under the eyes, and a protruding tongue. People with Down syndrome are subject to a variety of medical problems including heart abnormalities and thyroid gland dysfunction. Survival rates have been increased dramatically in recent years as problems specific to Down syndrome become known, allowing the early treatment. The life expectancy of people with Down syndrome now approaches that of people with out it. Usually it 's around 55 years old. You would have numerous abnormalities; it wouldn 't go over well in school. People don 't accustom to that very well in public schools. The genetic cause for Down syndrome is when a person inherits all or part of an extra copy of chromosome 21. Trisomy 21, the inheritance of an entire third copy of this chromosome, accounts for 95 percent of Down syndrome cases. Two other abnormalities each account for 2 to 3 percent of all cases. The first, translocation, takes place when a child inherits an extra piece of chromosome 21 attached to a different chromosome. The second, called mosaic Down syndrome, results when only some cells in the body have the extra chromosome. There is no cure for Down syndrome although prenatal tests are available to identify fetuses with the disorder. Down syndrome can be diagnosed just by looking at the baby at birth. The facial features and characteristics can tell you that. If the attending physician suspects Down syndrome, a karyotype a blood or tissue sample stained to show chromosomes grouped by size, number, and shape will be performed to verify the diagnosis. The most familiar physical traits of Down syndrome include: · Low muscle tone · Flat facial profile · Upward slant to the eyes · Abnormal shape and small size of the ears · Single deep
References: www.kidshealth.org (5 pgs.) Encarta Online Premium (2 pgs.)