ABCG2 and chronic myelogenous leukemia, BCR-ABL1 positive: The AA genotype of ABCG2 rs2231142 was not detected in CML patients, but individuals homozygous for the major allele (CC genotype) presented increased predisposition to CML (MD: OR = 1.601, 95%CI 1.034–2.480, p = 0.035).