Loss of heterozygosity at pseudoautosomal regions in human breast cancer and association with negative hormonal phenotype

To determine the possible involvement of X-linked genes in breast cancer, a group of human sporadic breast carcinomas were analyzed for loss of heterozygosity (LOH) at 12 polymorphic loci distributed along the whole chromosome X. LOH by at least one marker was observed in 14 of 46 informative cases and two regions of consistent LOH in 10 of 14 (71.4%) were identified at pseudoautosomal regions (PAR). Allelic losses in these regions significantly correlated with the absence of estrogen receptors (P-/PgR ^- when associated and provides some additional support for the existence of candidate tumor suppressor gene on PAR regions, whose alteration may play a role in breast cancer development and progression.