In the present study, based on the associations with cancers from previous literature, we examined the influence of four SNPs, rs3124591, rs11249433, rs1043994, and rs3830041 which are located within or in close proximity of NOTCH1, NOTCH2, NOTCH3 and NOTCH4 genes, respectively on BC and CRC susceptibility by comparing the genotypic distribution of these SNPs in cancer cases to that of healthy subjects from Saudi Arabia. The gene discussed is NOTCH1; the disease is breast cancer.