RT Journal Article
SR Electronic
T1 Frequent non-allelic gene conversion on the human lineage and its effect on the divergence of gene duplicates
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 135152
DO 10.1101/135152
A1 Arbel Harpak
A1 Xun Lan
A1 Ziyue Gao
A1 Jonathan K. Pritchard
YR 2017
UL http://biorxiv.org/content/early/2017/05/08/135152.abstract
AB Gene conversion is the unidirectional transfer of genetic sequence from a “donor” region to an “acceptor”. In non-allelic gene conversion (NAGC), the donor and the acceptor are at distinct genetic loci. Despite the role NAGC plays in various genetic diseases and the concerted evolution of many gene families, the parameters that govern NAGC are not well-characterized. Here, we survey duplicate gene families and identify converted tracts in 46% of them. These conversions reflect a significant GC-bias of NAGC. We develop a population-genetic model that exploits information from a long evolutionary history and use it to estimate the parameters that govern NAGC in humans: a mean conversion tract length of 250bp and a probability of 2.5 × 10−7 per generation for a nucleotide to be converted (an order of magnitude higher than point mutations). Despite this seemingly high rate, we show that NAGC has only a small average effect on the sequence divergence of duplicates. This work improves our understanding of NAGC mechanism and the role that it plays in the evolution of gene duplicates.