PT  - JOURNAL ARTICLE
AU  - Kamil S. Jaron
AU  - Jens Bast
AU  - T. Rhyker Ranallo-Benavidez
AU  - Marc Robinson-Rechavi
AU  - Tanja Schwander
TI  - Genomic features of asexual animals
AID  - 10.1101/497495
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 497495
4099  - http://biorxiv.org/content/early/2018/12/17/497495.short
4100  - http://biorxiv.org/content/early/2018/12/17/497495.full
AB  - Evolution under asexuality is predicted to impact genomes in numerous ways, but empirical evidence remains unclear. Case studies of individual asexual animals have reported peculiar genomic features which have been linked to asexuality, including high heterozygosity, a high abundance of horizontally acquired genes, a low transposable element load, and the presence of palindromes. However, it is unclear whether these features are lineage-specific or general consequences of asexuality. We reanalyzed published genomes of 24 asexual animals and found that not a single genome feature is systematically replicated across a majority of these species, suggesting that there is no genomic feature characteristic of asexuality. We found that only asexuals of hybrid origin were characterized by high heterozygosity levels. Asexuals that were not of hybrid origin appeared to be largely homozygous, independently of the cellular mechanism underlying asexuality. Overall, despite the importance of recombination rate variation for understanding the evolution of sexual animal genomes, the genome-wide absence of recombination does not appear to have the dramatic effects which are expected from classical theoretical models. The reasons for this are probably a combination of lineage-specific patterns, impact of the origin of asexuality, and a survivor bias of asexual lineages.AbbreviationsTEtransposable element;HGThorizontal gene transfer