Haplotype GWAS in Colorectal Cancer Patients with a Family History of Gastric or Prostate Cancer

Previous haplotype Genome Wide Association Studies (GWASs) have suggested several rare loci with a shared increased risk of colorectal, gastric, and prostate cancer. This study aimed to find out more about markers specifically addressing the shared risk of colorectal and gastric cancer, as well as the shared risk of colorectal and prostate cancer. One analysis used 426 colorectal cancer cases with gastric cancer, with no prostate cancer cases in their families, and another analysis used 324 colorectal cancer cases with prostate cancer but no gastric cancer among relatives. The computational program PLINK v1.07 was used for the analysis and for the calculation of corresponding ORs, standard errors, and 95% confidence intervals (CI). The study found support for the loci from previous studies and many new loci with a shared risk of colorectal cancer and gastric cancer. There were no significant loci from the second analysis for a shared risk of colorectal and prostate cancer. Altogether, more than 100 new loci with a shared risk of colorectal cancer and gastric cancer were suggested. A shared risk of colorectal and prostate cancer at some loci could not be ruled out. Haplotype GWAS has again demonstrated its ability to find rare risk loci mostly associated with coding genes.