Reversed sex-biased mutation rates for indels and base substitutions inDrosophila melanogaster

Abstract

1Sex biases in mutation rates may affect the rate of adaptive evolution. In many species, males 2 have higher mutation rates than females when single nucleotide variants (SNVs) are considered. 3In contrast, indel mutations in humans and chimpanzees are female-biased. In Drosophila 4 melanogaster, direct estimates of mutation rates did not uncover sex differences, but a recent 5 analysis suggested the presence of male-biased SNVs mutations. Here we study the sex-specific 6 mutation processes using mutation accumulation data from mismatch-repair deficient D. 7 melanogaster. We find that sex differences in flies are similar to the ones observed in humans: a 8 higher mutation rate for SNVs in males and a higher indel rate in females. These results have 9 major implications for the study of neutral variation and adaptation in Drosophila. 10 192