A marginally significant association was further observed in the validation stage using pre-diagnostic blood samples from the Mano-A-Mano cohort, as increased p16INK4a mRNA expression was associated with 1.28-fold increased risk of breast cancer (OR = 1.28; 95%CI: 0.98, 2.97; p = 0.053). This evidence concerns the gene CDKN2A and breast carcinoma.