1 out of every 691 live births
1 in every 1,000 babies that is born. 1 is the Down syndrome and 1,000 is the people that dont.
Disorders, such as Down's Syndrome, are caused by nondisjunction.
Down syndrome is generally the preferred spelling, although Down's syndrome is sometimes used in American sources.
Most cases of down syndrome are not inherited. Translocation Down syndrome can be inherited.
Down Syndrome Is In Your Brain.