Information about Down Syndrome
Information about Down Syndrome
Down syndrome is a genetic disease caused by three major factors, genetics, chromosome formation and cell division. Through scientific research, scientists have made vast discoveries on how to "treat" people with the disease and how to help families cope with a child with Down syndrome. Through our research we hope to make more people aware of Down syndrome, how it is caused, how they can help and what is being done to treat people with the disease, so that one day it may be "curable."
Down's syndrome was discovered in the late 19th century by John Langdon Down. His scholarly work published in 1866 earned him the recognition as the "father" of the syndrome. "Jerome Lejeune identified Down syndrome as a chromosomal anomaly. Down syndrome is an extra partial or complete 21st chromosome, which results in the characteristics associated with Down syndrome" (Madnick 2). "It is characterized by low muscle tone, flat facial profile, oblique palpebral fissures, dysplastic ear, single deep crease across the center of the palm, hyperflexibility, dysplastic middle phalanx of the fifth finger, epicanthal folds-small skin folds on the inner corner of the eyes, excessive space between large and second toe, and enlargement of tongue in relationship to size of mouth" (Madnick 5).
One of the causes of Down syndrome is genetics. "Genetics are grouped along rod-like structures called chromosomes. Normally, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent" (Madnick 2). However, in Down syndrome, the cells usually contain not 46, but 47 chromosomes; with the extra chromosome being a number 21. "Because 95 percent of all cases of Down syndrome occur because there are three copies of the 21st chromosome, it is referred to as "trisomy 21" (Madnick 2). Chromosomes can be studied by examining blood or tissue cells. Individual chromosomes are identified, stained, and numbered from largest to smallest; this visual display is known as a karyotype.
Another way that Down syndrome is caused is through cell division; usually through an error in non-disjunction. However, two other types of chromosomal abnormalities, mosaicism and translocation, are also implicated in Down syndrome-although to a lesser extent. Regardless of the...