title: The biological origin of mild mental retardation. A critical review.
abstract: The prevailing theory that normal intelligence and mild mental retardation are determined by multiple additive genes is critically reviewed in the light of findings from recent population studies. Discrepancies between theoretical concepts and reported data are noted, particularly those concerning frequency of mild mental retardation, sex ratio, and additional somatic and psychiatric handicaps in populations with mild mental retardation.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004812:Epidemiologic Methods; D000431:Ethanol / Q000009:adverse effects; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D007361:Intelligence Tests / Q000592:standards; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012424:Rural Population; D012737:Sex Factors; D012744:Sex Ratio; D014505:Urban Population
chemical_list: D000431:Ethanol