Gene duplication in the coral genus Acropora

Abstract

Whole Genome Duplications (WGD) pose major evolutionary events, giving rise to increased gene diversity. They have often been associated with major changes e.g. mass extinctions. The coral genus Acropora is a reef-building Hexacorallia species endangered by climate change with rich species diversity. Gene duplications in Acropora have been linked to the genus' resilience to bleaching events. Previously, WGD in Acropora has been suggested but has since been contended. The results here show that gene duplications in Acropora did not result from an independent WGD and that the number of duplications in the genus is likely due to multiple small-scale tandem duplications. We show that while gene duplications increased in the most recent common ancestor of multiple Hexacorallia species respectively, this is not unique to Acropora species and that the duplicated genes lack the synteny expected from duplicates arising from a WGD.