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Downs Syndrome

• A chromosome disorder associated either with an extra 21 or effective trisomy for 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 MENTAL RETARDATION. Cardiac gastrointestinal malformations, marked increase in incidence of LEUKEMIA, early onset ALZHEIMER DISEASE are also this condition. Pathologic features development NEUROFIBRILLARY TANGLES neurons deposition AMYLOID BETA-PROTEIN, similar pathology DISEASE. (Menkes, Textbook Child Neurology, 5th ed, p213)