Bloom syndrome and maternal uniparental disomy for chromosome 15

Authors

Trevor Woodage, Royal Prince Alfred Hospital
Madhuri Prasad, Royal Prince Alfred Hospital
Joanne W. Dixon, Wellington Regional Genetics Service
Roslyn E. Selby, Wellington Hospital
Dennis R. Romain, Wellington Regional Genetics Service
Letizia M. Columbano-Green, Wellington Regional Genetics Service
David Graham, Waikato Hospital
Peter K. Rogan, Penn State College of Medicine
James R. Seip, Penn State College of Medicine
Arabella Smith, Children's Hospital At Westmead
Ronald J. Trent, Royal Prince Alfred Hospital

Document Type

Article

Publication Date

7-19-1994

Journal

American Journal of Human Genetics

Volume

55

Issue

1

First Page

74

Last Page

80

Abstract

Bloom syndrome (BS) is an autosomal recessive disorder characterized by increases in the frequency of sister-chromatid exchange and in the incidence of malignancy. Chromosome-transfer studies have shown the BS locus to map to chromosome 15q. This report describes a subject with features of both BS and Prader-Willi syndrome (PWS). Molecular analysis showed maternal uniparental disomy for chromosome 15. Meiotic recombination between the two disomic chromosomes 15 has resulted in heterodisomy for proximal 15q and isodisomy for distal 15q. In this individual BS is probably due to homozygosity for a gene that is telomeric to D15S95 (15q25), rather than to genetic imprinting, the mechanism responsible for the development of PWS. This report represents the first application of disomy analysis to the regional localization of a disease gene. This strategy promises to be useful in the genetic mapping of other uncommon autosomal recessive conditions.