TY - JOUR
T1 - Drift-barrier hypothesis and mutation-rate evolution
AU - Sung, Way
AU - Ackerman, Matthew S.
AU - Miller, Samuel F.
AU - Doak, Thomas G.
AU - Lynch, Michael
PY - 2012/11/6
Y1 - 2012/11/6
N2 - Mutation dictates the tempo and mode of evolution, and like all traits, the mutation rate is subject to evolutionary modification. Here, we report re fined estimates of the mutation rate for a prokaryote with an exceptionally small genome and for a unicellular eukaryote with a large genome. Combined with prior results, these estimates provide the basis for a potentially unifying explanation for the wide range in mutation rates that exists among organisms. Natural selection appears to reduce the mutation rate of a species to a level that scales negatively with both the effective population size (Ne), which imposes a drift barrier to the evolution of molecular refinements, and the genomic content of coding DNA, which is proportional to the target size for deleterious mutations. As a consequence of an expansion in genome size, some microbial eukaryotes with large Ne appear to have evolved mutation rates that are lower than those known to occur in prokaryotes, but multicellular eukaryotes have experienced elevations in the genome-wide deleterious mutation rate because of substantial reductions in Ne.
AB - Mutation dictates the tempo and mode of evolution, and like all traits, the mutation rate is subject to evolutionary modification. Here, we report re fined estimates of the mutation rate for a prokaryote with an exceptionally small genome and for a unicellular eukaryote with a large genome. Combined with prior results, these estimates provide the basis for a potentially unifying explanation for the wide range in mutation rates that exists among organisms. Natural selection appears to reduce the mutation rate of a species to a level that scales negatively with both the effective population size (Ne), which imposes a drift barrier to the evolution of molecular refinements, and the genomic content of coding DNA, which is proportional to the target size for deleterious mutations. As a consequence of an expansion in genome size, some microbial eukaryotes with large Ne appear to have evolved mutation rates that are lower than those known to occur in prokaryotes, but multicellular eukaryotes have experienced elevations in the genome-wide deleterious mutation rate because of substantial reductions in Ne.
KW - Random genetic drift
KW - Replication fidelity
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U2 - 10.1073/pnas.1216223109
DO - 10.1073/pnas.1216223109
M3 - Article
C2 - 23077252
AN - SCOPUS:84868599895
SN - 0027-8424
VL - 109
SP - 18488
EP - 18492
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 - 45
ER -