title: Frequency of rare fragile sites among mentally subnormal schoolchildren.
abstract: The frequency of rare fragile sites was studied among 240 children in special schools for subnormal intelligence (IQ 52-85). 1/130 boys studied (0.8%) had the fragile site at Xq27.3 while it was not found in any girl (0/110). In two children an autosomal rare fragile site at 2q11.2 (2/240, 0.8%) was seen. In addition a constitutional chromosome abnormality was found in a further seven children (7/240, 2.9%).
mesh_terms: D000293:Adolescent; D002648:Child; D002869:Chromosome Aberrations; D043283:Chromosome Fragile Sites; D002873:Chromosome Fragility; D002889:Chromosomes, Human, Pair 2; D005260:Female; D005387:Finland; D005600:Fragile X Syndrome / Q000453:epidemiology; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male