Given rs3731249 was located in the coding region of an important tumor suppressor gene CDKN2A, and induced alanine to threonine alteration in 148 position (A148T), allelic imbalanced was evaluated in somatic leukemia cells from individuals with heterozygous genotype of rs3731249 in 15 and 35 cases in two independent studies and indicated the variant allele preferentially retained significantly through either copy number variation or post-transcriptional inactivation during leukemogenesis. The gene discussed is CDKN2A; the disease is leukemia.