What is Down syndrome?
Down syndrome also known as Trisomy 21 is a chromosomal condition where a person possesses extra genetic material that is: an extra complete or fractional duplicate of chromosome 21. It is one of the most common birth defects. It affects 1 in 800 to 1 in 1000 live born infants. Close to half of all affected children develop heart defects right from birth (Goldstein 71).
Causes
Down syndrome is typically caused by non-disjunction; when one of the three types of abnormal cell division involving chromosome 21 occurs. Non-disjunction occurs when a pair of chromosomes fails to detach during sperm or egg formation. After ...