title: Polymorphisms in a desaturase 2 ortholog associate with cuticular hydrocarbon and male mating success variation in a natural population of Drosophila serrata.
abstract: Elucidating the nature of genetic variation underlying both sexually selected traits and the fitness components of sexual selection is essential to understanding the broader consequences of sexual selection as an evolutionary process. To date, there have been relatively few attempts to connect the genetic variance in sexually selected traits with segregating DNA sequence polymorphisms. We set out to address this in a well-characterized sexual selection system--the cuticular hydrocarbons (CHCs) of Drosophila serrata--using an indirect association study design that allowed simultaneous estimation of the genetic variance in CHCs, sexual fitness and single nucleotide polymorphism (SNP) effects in an outbred population. We cloned and sequenced an ortholog of the D. melanogaster desaturase 2 gene, previously shown to affect CHC biosynthesis in D. melanogaster, and associated 36 SNPs with minor allele frequencies > 0.02 with variance in CHCs and sexual fitness. Three SNPs had significant multivariate associations with CHC phenotype (q-value < 0.05). At these loci, minor alleles had multivariate effects on CHCs that were weakly associated with the multivariate direction of sexual selection operating on these traits. Two of these SNPs had pleiotropic associations with male mating success, suggesting these variants may underlie responses to sexual selection due to this locus. There were 15 significant male mating success associations (q-value < 0.1), and interestingly, we detected a nonrandom pattern in the relationship between allele frequency and direction of effect on male mating success. The minor-frequency allele usually reduced male mating success, suggesting a positive association between male mating success and total fitness at this locus.
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia.
authors.forename: J
authors.initials: J
authors.lastname: Ivory-Church
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia.|Institute of Health and Biomedical Innovation and School of Biomedical Sciences, Queensland University of Technology, Kelvin Grove, Qld, Australia.
authors.forename: F D
authors.initials: FD
authors.lastname: Frentiu
authors.affiliation: School of Biological Sciences, The University of Queensland, St. Lucia, Qld, Australia.
authors.forename: S F
authors.initials: SF
authors.lastname: Chenoweth
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics*; D044943:Fatty Acid Desaturases / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D006838:Hydrocarbons / Q000378:metabolism; D008297:Male; D052586:Mating Preference, Animal; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide; D012726:Sexual Behavior, Animal
chemical_list: D029721:Drosophila Proteins; D006838:Hydrocarbons; D044943:Fatty Acid Desaturases; C499595:desat2 protein, Drosophila
keywords: Drosophila serrata; cuticular hydrocarbons; desaturase 2; mutation-selection balance; sexual selection