SYNDROME, DOWN

A common disorder due to a chromosome abnormality and specfically due to an extra chromosome number 21 (trisomy 21). Down syndrome includes mental retardation, a characteristic face, and multiple malformations. It is associated with a major risk for heart problems, a lesser risk of duodenal atresia (part of the intestines not developed), and a minor but still significant risk of acute leukemia. The name Down syndrome comes from the 19th century English doctor Langdon Down, a misnomer since he was curiously enough not the first person to describe the condition and, in great error, attributed the condition to a "reversion" to the mongoloid race. Hence, the old name mongolism, now considered slang.