Potential impact of primate-specific SVA retrotransposons during the evolution of human cognitive function

Abstract

The SVA family of hominid-specific non-LTR retrotransposon comprises the youngest group of transposable elements in the human genome. The propagation of the most ancient SVA subfamily took place about 13.5 million years ago, and the youngest SVA subfamily appeared in the human genome after the human/chimpanzee divergence. Functional analysis of genes associated with SVA insertions demonstrated their link to multiple ontological categories, with one of the major categories being attributed to brain function. Further analysis of this subset demonstrated that SVA elements expanded their presence in the human genome at different stages of hominoid evolution and were associated with progressively evolving behavioral features that indicate a potential impact of SVA propagation on the cognitive ability of a modern human. Our analysis suggests a potential role of SVAs in the evolution of human central nervous system and especially in the emergence of functional trends relevant to social and parental behavior. Coevolution of behavioral features and reproductive functions are suggested by our analysis and discussed.