TY - JOUR
T1 - Comparative evolutionary genetics of spontaneous mutations affecting fitness in rhabditid nematodes
AU - Baer, Charles F.
AU - Shaw, Frank
AU - Steding, Catherine
AU - Baumgartner, Margaret
AU - Hawkins, Alicia
AU - Houppert, Andrew
AU - Mason, Nicole
AU - Reed, Marissa
AU - Simonelic, Kevin
AU - Woodard, Wayne
AU - Lynch, Michael
PY - 2005/4/19
Y1 - 2005/4/19
N2 - Deleterious mutations are of fundamental importance to all aspects of organismal biology. Evolutionary geneticists have expended tremendous effort to estimate the genome-wide rate of mutation and the effects of new mutations on fitness, but the degree to which genomic mutational properties vary within and between taxa is largely unknown, particularly in multicellular organisms. Beginning with two highly inbred strains from each of three species in the nematode family Rhabditidae (Caenorhabditis briggsae, Caenorhabditis elegans, and Oscheius myriophila), we allowed mutations to accumulate in the relative absence of natural selection for 200 generations. We document significant variation in the rate of decay of fitness because of new mutations between strains and between species. Estimates of the per-generation mutational decay of fitness were very consistent within strains between assays 100 generations apart. Rate of mutational decay in fitness was positively associated with genomic mutation rate and negatively associated with average mutational effect. These results provide unambiguous experimental evidence for substantial variation in genome-wide properties of mutation both within and between species and reinforce conclusions from previous experiments that the cumulative effects on fitness of new mutations can differ markedly among related taxa.
AB - Deleterious mutations are of fundamental importance to all aspects of organismal biology. Evolutionary geneticists have expended tremendous effort to estimate the genome-wide rate of mutation and the effects of new mutations on fitness, but the degree to which genomic mutational properties vary within and between taxa is largely unknown, particularly in multicellular organisms. Beginning with two highly inbred strains from each of three species in the nematode family Rhabditidae (Caenorhabditis briggsae, Caenorhabditis elegans, and Oscheius myriophila), we allowed mutations to accumulate in the relative absence of natural selection for 200 generations. We document significant variation in the rate of decay of fitness because of new mutations between strains and between species. Estimates of the per-generation mutational decay of fitness were very consistent within strains between assays 100 generations apart. Rate of mutational decay in fitness was positively associated with genomic mutation rate and negatively associated with average mutational effect. These results provide unambiguous experimental evidence for substantial variation in genome-wide properties of mutation both within and between species and reinforce conclusions from previous experiments that the cumulative effects on fitness of new mutations can differ markedly among related taxa.
KW - Caenorhabditis briggsae
KW - Caenorhabditis elegans
KW - Deleterious mutation
KW - Mutation accumulation
KW - Oscheius myriophila
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U2 - 10.1073/pnas.0406056102
DO - 10.1073/pnas.0406056102
M3 - Article
C2 - 15809433
AN - SCOPUS:20244378694
SN - 0027-8424
VL - 102
SP - 5785
EP - 5790
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 16
ER -