Down's syndrome is a genetic condition involving an extra chromosome, this change occurs around the time of conception. A person with Down's syndrome has forty-seven chromosomes instead of the usual forty-six. A relatively common genetic disorder, Down's strikes 1 out of 600 babies. In 95 percent of all cases, the disorder originates with the egg, not the sperm, and the only known risk factor is advanced maternal age-at age 35, a woman has 1 chance in 117 of having a baby with Down's; at 40, her odds are 1 in 34.
(Graves, 1990)
People with Down's syndrome all have a certain degree of learning disability . This means that they develop and learn more slowly than other children. However, most children with Down's syndrome today will walk and talk, many will read and write, go to ordinary school, and look forward to a semi-independent adult life. (Platt and Carlson, 1992)
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