How does geographical distance translate into genetic distance?

Verónica Miró Pina (1, 2) , Emmanuel Schertzer (1, 2)

1 CIRB - Centre interdisciplinaire de recherche en biologie
2 LPSM (UMR_8001) - Laboratoire de Probabilités, Statistique et Modélisation

Geographic structure can affect patterns of genetic differentiation and speciation rates. In this article, we investigate the dynamics of genetic distances in a geographically structured metapopulation. We model the metapopulation as a weighted directed graph, with N vertices corresponding to N homogeneous subpopulations. The dynamics of the genetic distances is then controlled by two types of transitions -mutation and migration events between islands. Under a large population-long chromosome limit, we show that the genetic distance between two subpopulations converges to a deterministic quantity that can asymptotically be expressed in terms of the hitting time between two random walks in the metapopulation graph. Our result shows that the genetic distance between two subpopulations does not only depend on the direct migration rates between them but on the whole metapopulation structure.

Mots clés: Metapopulation structure; Graph distance; Genetic distance

Domaines: Probabilités [math.PR]; Evolution [q-bio.PE]

Verónica Miró Pina, Emmanuel Schertzer. How does geographical distance translate into genetic distance?. Stochastic Processes and their Applications, 2018, 129 (10), pp.3893-3921. ⟨10.1016/j.spa.2018.11.004⟩. ⟨hal-01484800⟩