Institute of Evolutionary Sciences
Department of Genomics
Place Eugene Bataillon
Abstracts (first author)
Mosaic genomes in time and space revealed by large-scale targeted sequencing in Mytilus mussels
Marine species with high rates of dispersal have often had complex histories of fragmentation and colonization. These can subtly modify the genomic barriers to gene flow between hybridizing populations, leading to mosaic patterns of genetic divergence. The Mytilus complex of marine mussels exemplifies these processes, as it includes populations with a wide range of divergences, and has a world-wide distribution, which has led to multiple independent contacts between the same species pairs in different ecological contexts. To understand patterns of genomic divergence in Mytilus, we conducted a large-scale targeted genomic capture experiment, investigating fine-scale variation in genetic diversity. Our target genomic regions included islands of divergence and valleys of introgression identified from Fst scans and BAC sequencing, as well as randomly chosen controls. Each region was sequenced in twelve genetic backgrounds from three Mytilus species, distributed throughout the northern hemisphere. By studying variation in gene genealogies, our results illustrate how genome mosaicism varies in time and space. We also compare nuclear coding genes of known function (including immunity, cyto-nuclear interactions and nucleoporins) to randomly chosen control genes.