title: [Clinico-genetic diagnosis of severe mental retardation].
abstract: Among 330 patients with severe mental retardation who were consulted at random for medico-genetic purposes (excluding phenylketonuria and Down's disease), 27,3% constituted retarded patients due to genetic diseases, 10%--to exogenous factors. Families with a high genetical risk (25%-50% for sibs) constituted 20%. In the group of patients with severe mental retardation, but without signs of organic lesion in the neurological state or multiple congenital anomalies, there was a higher percentage of consanguineous parents and affected sibs, than in the group of patients with residual-organic neurological changes and in the group of patients with the so-called malformation retardation syndromes.
mesh_terms: D000015:Abnormalities, Multiple / Q000150:complications; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000150:complications / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D009154:Mutation; D012306:Risk; D012729:Sex Chromosome Aberrations; D013577:Syndrome
vernacular_title: Kliniko-geneticheskaia diagnostika glubokoĭ umstvennoĭ otstalosti.