Haplotype Blocks in 8q24 Gene Desert Linked to Cancer
Researchers identify five blocks associated with prostate, breast, colorectal and ovarian cancer
WEDNESDAY, June 25 (HealthDay News) -- Five specific loci within the 8q24 gene desert are associated with an increased risk of various cancers, according to research published in the July 2 issue of the Journal of the National Cancer Institute.
Maya Ghoussaini, Ph.D., of the University of Cambridge in Cambridge, U.K., and colleagues genotyped the nine previously reported cancer-associated single nucleotide polymorphisms (SNPs) across the region in four case-control sets of patients: 1,854 with prostate cancer and 1,894 controls; 2,270 with breast cancer and 2,280 controls; 2,299 with colorectal cancer and 2,284 controls; and 1,975 with ovarian cancer and 3,411 controls.
The researchers identified five different haplotype blocks that were specifically associated with risks of various cancers, including one that was solely associated with the risk of breast cancer, three that were solely associated with the risk of prostate cancer, and one that was associated with the risk of prostate, colorectal and ovarian cancer, but not breast cancer.
"Despite their strong associations with cancer, it is not known whether the SNPs tested here are causal variants or are simply markers that are correlated with the causal variants in each region," the authors conclude. "Resequencing and fine mapping of each of the haplotype blocks, followed by functional characterization studies, may ultimately identify the causal variants and reveal their mechanisms in cancer susceptibility and pathogenesis. If this 8q24 locus is truly a gene desert, it points to a very long-range mode of action for these variants that had previously been considered unlikely."