title: Fragile site X chromosomes and X-linked mental retardation in severely retarded boys in a northern  Swedish county. A prevalence study.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D012729:Sex Chromosome Aberrations / Q000453:epidemiology*; D013548:Sweden; D014960:X Chromosome