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July 06, 2008
Posted by charles
( 0 ratings )
Human cells normally contain 23 pairs of chromosomes. One chromosome in each pair comes from your father, the other from your mother.
The cause of Down syndrome is one of three types of abnormal cell division involving the 21st chromosome. All three abnormalities result in extra genetic material from chromosome 21, which is responsible for the characteristic features and developmental problems of Down syndrome.
The cause of Down syndrome is one of three types of abnormal cell division involving the 21st chromosome. All three abnormalities result in extra genetic material from chromosome 21, which is responsible for the characteristic features and developmental problems of Down syndrome.
...read the rest here.
A couple of other good sources are here and here.
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