Tao and colleagues [18] evaluated whether early-life factors are associated with promoter methylation of the CDH1 (which encodes the cell-adhesion protein cadherin-1), CDKN2A (which encodes important tumour suppression proteins such as p14 and p16) and RARB (which encodes a receptor for retinoic acid) genes. This evidence concerns the gene RARB and neoplasm.