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Down's syndrome[′dau̇nz ‚sin‚drōm]
a form of congenital feeblemindedness; first described in 1866 by the English physician L. Down, who called the condition mongolism.
An anomalous set of chromosomes lies at the basis of Down’s syndrome. Persons affected with the syndrome have 47 chromosomes in their cells instead of the usual 46 (that is, three instead of two chromosomes in the 21st pair). This disruption (trisomy) of the karyotype occurs when a separation of the chromosomes of the 21st pair has occurred during maturation of the germ cell in the mother and the formed egg cell contains 24 chromosomes; the causes have not as yet been studied. Patients with Down’s syndrome present a characteristic appearance: round face, short nose with a wide bridge, slanted eyes with a skin fold at the corner, half-opened mouth, large tongue, sparse teeth, and an anteriopos-teriorly flattened head. Muscular weakness, loose joints, retarded physical development, distended abdomen, and underdeveloped sexual organs are also noted. Down’s syndrome is often accompanied by heart disease and impairment of vision. The degree of mental underdevelopment varies from complete idiocy to slight degrees of mental deficiency. Patients are inclined to imitativeness; they are basically affectionate, good-natured, and friendly. Treatment is largely ineffective; hormonal preparations and glutamic acid are used. Education is offered in auxiliary schools. Occupational therapy plays an important role in the treatment and education of patients.
N. D. MIKERINA