GSTP1 and Cirrhosis: Our previous work in Guatemala found that men had significantly higher circulating levels of AFB1-lys adducts than women.3 Animal studies have shown that castration of male rats reduced the hepatic metabolism of AFB1 (approximately 50%),41 and have reported that male rats are more likely to develop AFB-induced glutathione-S-transferase-P-positive hepatocytes (a marker of preneoplastic foci) than do female rats.42 This evidence may help to explain the current finding of the AFB1–cirrhosis association being more pronounced among men than women.