Enlargement of the long arm of a B-group chromosome (Bq+) in a boy aged nine years.
D000015:Abnormalities, Multiple / Q000235:genetics*; D002648:Child; D002869:Chromosome Aberrations / Q000235:genetics*; D025063:Chromosome Disorders; D002875:Chromosomes / Q000032:analysis; D002905:Chromosomes, Human, 4-5; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D007621:Karyotyping; D007962:Leukocytes / Q000166:cytology; D008297:Male; D010375:Pedigree