Originally published as Genetics Published Articles Ahead of Print on October 22, 2006.
Genetics, Vol. 174, 2129-2136, December 2006, Copyright © 2006
doi:10.1534/genetics.106.065508
Low Impact of Germline Transposition on the Rate of Mildly Deleterious Mutation in Caenorhabditis elegans
Mattieu Bégin and
Daniel J. Schoen1
Department of Biology, McGill University, Montreal, Quebec H3A 1B1, Canada
1 Corresponding author: Department of Biology, McGill University, 1205 Dr. Penfield Ave., Montreal, QC H3A 1B1, Canada.
E-mail: daniel.schoen{at}mcgill.ca
Little is known about the role of transposable element (TE) insertion in the production of mutations with mild effects on fitness, the class of mutations thought to be central to the evolution of many basic features of natural populations. We propagated mutation-accumulation (MA) lines of two RNAi-deficient strains of Caenorhabditis elegans that exhibit germline transposition. We show here that the impact of TE activity was to raise the level of mildly deleterious mutation by 2- to 8.5-fold, as estimated from fecundity, longevity, and body length measurements, compared to that observed in a parallel MA experiment with a control strain characterized by a lack of germline transposition. Despite this increase, the rate of mildly deleterious mutation was between one and two orders of magnitude lower than the rate of TE accumulation, which was approximately two new insertions per genome per generation. This study suggests that high rates of TE activity do not necessarily translate into high rates of detectable nonlethal mutation.
Copyright © 2006 by the Genetics Society of America.