The PPARG Pro12Ala amino acid substitution abolishes the alcohol-specific regulation of PPARG presumably by modifying the interaction with the cofactor PGC-1α.33 The interaction has not been reproduced for other CRC cohorts, but the finding is indirectly supported by the fact that interaction between PPARG Pro12Ala and alcohol intake was also found in relation to breast cancer.33,35,. This evidence concerns the gene PPARGC1A and breast cancer.