RT Journal Article SR Electronic T1 Natural Allelic Variations of Xenobiotic Enzymes Pleiotropically Affect Sexual Dimorphism in Oryzias latipes JF bioRxiv FD Cold Spring Harbor Laboratory SP 000661 DO 10.1101/000661 A1 Takafumi Katsumura A1 Shoji Oda A1 Shigeki Nakagome A1 Tsunehiko Hanihara A1 Hiroshi Kataoka A1 Hiroshi Mitani A1 Shoji Kawamura A1 Hiroki Oota YR 2013 UL http://biorxiv.org/content/early/2013/11/19/000661.abstract AB Sexual dimorphisms, which are phenotypic differences between males and females, are driven by sexual selection [1, 2]. Interestingly, sexually selected traits show geographic variations within species despite strong directional selective pressures [3, 4]. However, genetic factors that regulate varied sexual differences remain unknown. In this study, we show that polymorphisms in cytochrome P450 (CYP) 1B1, which encodes a xenobiotic-metabolising enzyme, are associated with local differences of sexual dimorphisms in the anal fin morphology of medaka fish (Oryzias latipes). High and low activity CYP1B1 alleles increased and decreased differences in anal fin sizes, respectively. Behavioural and phylogenetic analyses suggest maintenance of the high activity allele by sexual selection, whereas the low activity allele may have evolved by positive selection due to by-product effects of CYP1B1. The present data can elucidate evolutionary mechanisms behind genetic variations in sexual dimorphism and indicate pleiotropic effects of xenobiotic enzymes.