Down's Syndrome - a brief outline

Down's Syndrome is caused by and extra Chromosome 21, and is visible under a light microscope.

Sometimes referred to as trisomy 21, since it involves three genes on chromosome 21. It is the only chromosomal trisomy that is compatible with life beyond a few months. Most individuals with Down's Syndrome live to adulthood, although they have increased risk of heart disease and Alzheimer's diseases. It is the most common cause of mental retardation  occurring in about 1 in every 800 live births , incidence increases in the offspring of women over 35. Easily diagnosed prenatally.

This is a page from created by A. J. Palmer.
This page was updated on 2nd December 2002