A chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21. Clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, Simian crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)

Descriptor ID	D004314
MeSH Number(s)	C10.597.606.643.220 C16.131.077.327 C16.131.260.260 C16.320.180.260
Concept/Terms	Down Syndrome Down Syndrome Syndrome, Down Mongolism Trisomy 21 47,XX,+21 47,XY,+21 Down's Syndrome Downs Syndrome Syndrome, Down's Trisomy G Trisomy 21, Mitotic Nondisjunction Trisomy 21, Mitotic Nondisjunction Down Syndrome, Partial Trisomy 21 Down Syndrome, Partial Trisomy 21 Partial Trisomy 21 Down Syndrome Trisomy 21, Meiotic Nondisjunction Trisomy 21, Meiotic Nondisjunction

Below are MeSH descriptors whose meaning is more general than "Down Syndrome".

Below are MeSH descriptors whose meaning is related to "Down Syndrome".

Below are MeSH descriptors whose meaning is more specific than "Down Syndrome".