DO VARIATIONS IN SUBSTITUTION RATES AND MALE MUTATION BIAS CORRELATE WITH LIFE-HISTORY TRAITS? A STUDY OF 32 MAMMALIAN GENOMES

Authors

  • Melissa A. Wilson Sayres,

    1. Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
    2. Center for Comparative Genomics and Bioinformatics and Center for Medical Genomics, The Pennsylvania State University, University Park, Pennsylvania 16802
    3. Integrative Biosciences Program, The Pennsylvania State University, University Park, Pennsylvania 16802
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  • Chris Venditti,

    1. Department of Biological Sciences, University of Hull, Hull, HU6 7RX, United Kingdom
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  • Mark Pagel,

    1. School of Biological Sciences, University of Reading, Reading, Berkshire, RG6 6BX, United Kingdom
    2. Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501
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  • Kateryna D. Makova

    1. Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
    2. Center for Comparative Genomics and Bioinformatics and Center for Medical Genomics, The Pennsylvania State University, University Park, Pennsylvania 16802
    3. Integrative Biosciences Program, The Pennsylvania State University, University Park, Pennsylvania 16802
    4. E-mail: kdm16@psu.edu
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Abstract

Life-history traits vary substantially across species, and have been demonstrated to affect substitution rates. We compute genome-wide, branch-specific estimates of male mutation bias (the ratio of male-to-female mutation rates) across 32 mammalian genomes and study how these vary with life-history traits (generation time, metabolic rate, and sperm competition). We also investigate the influence of life-history traits on substitution rates at unconstrained sites across a wide phylogenetic range. We observe that increased generation time is the strongest predictor of variation in both substitution rates (for which it is a negative predictor) and male mutation bias (for which it is a positive predictor). Although less significant, we also observe that estimates of metabolic rate, reflecting replication-independent DNA damage and repair mechanisms, correlate negatively with autosomal substitution rates, and positively with male mutation bias. Finally, in contrast to expectations, we find no significant correlation between sperm competition and either autosomal substitution rates or male mutation bias. Our results support the important but frequently opposite effects of some, but not all, life-history traits on substitution rates.

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