title: Minor chromosome variations and selected heteromorphisms in 200 unclassifiable mentally retarded patients and 200 normal controls.
abstract: Lymphocyte chromosome preparations from 200 mentally retarded children and 200 normal adult controls were analyzed by G-, Q-, and C-banding techniques for minor chromosome variations (G and Q) and selected heteromorphisms (G and C). Minor variations scored included inv(9), prominent or decreased short arms and/or satellites on acrocentric chromosomes, and 17 ph. C heteromorphisms analyzed included those involving 1qh, 9zh, and 16zh regions. Length variations of Yq were scored on G-banded karyo types. No significant differences in frequencies of scored minor variations or heteromorphisms were noted between the retarded and control populations.
mesh_terms: D002648:Child; D002869:Chromosome Aberrations; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008214:Lymphocytes; D010641:Phenotype