A reassessment of explanations for discordant introgressions of mitochondrial and nuclear genomes

Timothée Bonnet (1) , Raphaël Leblois (2) , Francois Rousset (3) , Pierre-André Crochet (4)

1 CEBC - Centre d'Études Biologiques de Chizé - UMR 7372
2 UMR CBGP - Centre de Biologie pour la Gestion des Populations
3 UMR ISEM - Institut des Sciences de l'Evolution de Montpellier
4 CEFE - Centre d’Ecologie Fonctionnelle et Evolutive

Examples of massive mitochondrial introgressions combined with no or very limited nuclear introgressions (i.e. mito-nuclear discordance) are accumulating, stimulating the development of various hypotheses to explain this pattern. On the one hand, selective hypotheses propose a selective advantage of the introgressing mitochondrial variants, or counter-selection of the nuclear genome; On the other hand, neutral hypotheses invoke sex-biased processes and/or drift and/or spatial invasions. The neutral hypotheses however are mostly verbal and have not been quantitatively evaluated. Here we reassess all these hypotheses using simulations under a wide range of demographic and genetic scenarios.

Domaines: Evolution [q-bio.PE]; Génétique des populations [q-bio.PE]

Timothée Bonnet, Raphaël Leblois, Francois Rousset, Pierre-André Crochet. A reassessment of explanations for discordant introgressions of mitochondrial and nuclear genomes. Conférence Jacques Monod : Coalescence des approches théoriques et expérimentales en génomique évolutive et biologie des systèmes, Oct 2016, Roscoff, France. ⟨hal-02932269⟩