Testing for fitness epistasis in a transplant experiment identifies a candidate adaptive locus in Timema stick insects

Archive ouverte

Villoutreix, Romain | de Carvalho, Clarissa | Gompert, Zachariah | Parchman, Thomas | Feder, Jeffrey | Nosil, Patrik

Edité par CCSD ; Royal Society, The -

International audience. Identifying the genetic basis of adaptation is a central goal of evolutionary biology. However, identifying genes and mutations affecting fitness remains challenging because a large number of traits and variants can influence fitness. Selected phenotypes can also be difficult to know a priori , complicating top–down genetic approaches for trait mapping that involve crosses or genome-wide association studies. In such cases, experimental genetic approaches, where one maps fitness directly and attempts to infer the traits involved afterwards, can be valuable. Here, we re-analyse data from a transplant experiment involving Timema stick insects, where five physically clustered single-nucleotide polymorphisms associated with cryptic body coloration were shown to interact to affect survival. Our analysis covers a larger genomic region than past work and revealed a locus previously not identified as associated with survival. This locus resides near a gene, Punch ( Pu ) , involved in pteridine pigments production, implying that it could be associated with an unmeasured coloration trait. However, by combining previous and newly obtained phenotypic data, we show that this trait is not eye or body coloration. We discuss the implications of our results for the discovery of traits, genes and mutations associated with fitness in other systems, as well as for supergene evolution. This article is part of the theme issue ‘Genetic basis of adaptation and speciation: from loci to causative mutations’.

Consulter en ligne

Suggestions

Du même auteur

Complex evolutionary processes maintain an ancient chromosomal inversion

Archive ouverte | Nosil, Patrik | CCSD

International audience. Genome re-arrangements such as chromosomal inversions are often involved in adaptation. As such, they experience natural selection, which can erode genetic variation. Thus, whether and how in...

Ecology shapes epistasis in a genotype–phenotype–fitness map for stick insect colour

Archive ouverte | Nosil, Patrik | CCSD

International audience

Large-scale mutation in the evolution of a gene complex for cryptic coloration

Archive ouverte | Villoutreix, Romain | CCSD

International audience. How stick insects got their colors Stick insects of the genus Timema show variations in color that are likely due to selection for camouflage on their plant hosts. Some species are only brown...

Chargement des enrichissements...