Down Syndrome
Background
Down Syndrome Background
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Disease Etiology
Down syndrome is a condition affecting the body’s cell chromosomes (1,2). A typical person has 23 pairs of chromosomes. Down syndrome is a condition where an error happens during cell division, causing an abnormality in the 21st chromosome (1,2). There are three types of Down syndrome and two different mechanisms that result in this abnormality (3).
Trisomy 21
Nondisjunction is prevalent in most cases of Down syndrome and causes Trisomy 21, in which an extra copy of the 21st