
Dictionary » D » Downs syndrome Downs syndromeDowns syndrome (Science: genetics, syndrome) a congenital disorder in which a person is born with three copies of chromosome 21 (trisomy 21). clinical features include moderate to severe mental retardation, slanting eyes, a broad short skull, broad hands and short fingers. Other congenital abnormalities include heart defects, oesophageal atresia and an increased incidence of acute lymphocytic leukaemia. trisomy 21 can be detected in the first few months of pregnancy by amniocentesis. Risk factors include prior child with downs syndrome and mothers who become pregnant after age 40. This disorder was formerly known as mongolism. Incidence: 1 in 1000 births. A congenital disorder caused by having an extra 21st chromosome; results in a flat face and short stature and mental retardation.A genetic defect caused by non-disjunction at meiosis in humans resulting in one extra chromosome (3x21 chromosomes) in the carrier. Sufferers express characteristics such as heart defects, mental retardation and stunted growth. ![]()
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