title: Cytogenetic studies in Down syndrome.
abstract: Cytogenetic studies were carried out in 645 patients with Down syndrome. Free trisomy of chromosome 21 was present in 600 cases (93%). Translocation karyotypes were observed in 26 cases (4%). Seventeen patients (2.6%) had mosaicism. Two (0.3%) patients had additional karyotypic abnormalities along with trisomy 21.
authors.affiliation: Department of Pediatrics, All India Institute of Medical Sciences, New Delhi.
authors.forename: I C
authors.initials: IC
authors.lastname: Verma
authors.forename: S
authors.initials: S
authors.lastname: Mathew
authors.forename: R
authors.initials: R
authors.lastname: Elango
authors.forename: A
authors.initials: A
authors.lastname: Shukla
mesh_terms: D002869:Chromosome Aberrations / Q000453:epidemiology / Q000235:genetics*; D025063:Chromosome Disorders; D002883:Chromosomes, Human, Pair 14; D002884:Chromosomes, Human, Pair 15; D002891:Chromosomes, Human, Pair 21; D002892:Chromosomes, Human, Pair 22; D004314:Down Syndrome / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D014178:Translocation, Genetic / Q000235:genetics*