Most mutations that strike genes and other adapted regions of a genome are expected to be deleterious because there are more ways to break a gene than to improve it. A strongly deleterious mutation causes little net harm because it is quickly eliminated by selection, but a weakly deleterious mutation may drift to high frequency or even fix, depending on the population size, the strength of selection, and the indirect effects of selection at other sites in the mutation's genomic neighborhood. Thus many weakly deleterious mutations could circulate at intermediate frequencies, degrading fitness substantially. This process is expected to warp mitochondrial genome genealogies in three different ways, and the mitochondria of whale lice show all of the patterns predicted by our models. We are extending this theoretical and empirical system to estimate the complete distribution of mutational effect sizes. Eventually we hope to understand how weakly selected variation interferes with ecological and social adaptation.
- Mitochondrial population genomics of whale lice (Amphipoda, Cyamidae)
- Mildly deleterious mutations as obstacles to adaptation
- O'Fallon BD, Seger J, Adler FR. (2010) A continuous-state coalescent and the impact of weak selection on the structure of gene genealogies. Mol. Biol. Evol. 27(5):1162-1172. DOI:10.1093/molbev/msq006.
- Seger J, Smith WA, Perry JJ, Hunn J, Kaliszewska ZA, La Sala L, Pozzi L, Rowntree VJ, Adler FR. (2010) Gene genealogies strongly distorted by weakly selected mutations in constant environments. Genetics 184:529-545. DOI: 10.1534/genetics.109.103556.
- Valenzuela LO, Sironi M, Rowntree VJ, Seger J. (2009) Isotopic and genetic evidence for culturally inherited site fidelity to feeding grounds in southern right whales (Eubalaena australis). Molecular Ecology 18:782-791, DOI: 10.1111/j.1365-294X.2008.04069.x
- Kaliszewska ZA, Seger J, Rowntree VJ, Barco SG, Benegas R, Best PB, Brown MW, Brownell RL Jr, Carribero A, Harcourt R, Knowlton AR, MarshallTilas K, Patenaude NJ, Rivarola M, Schaeff CM, Sironi M, Smith WA, Yamada TK (2005) Population histories of right whales (Cetacea: Eubalaena) inferred from mitochondrial sequence diversities and divergences of their whale lice (Amphipoda: Cyamus). Molecular Ecology 14:3439-3456.
- Roth JR, Kofoid E, Roth FP, Berg OG, Seger J, Andersson DI (2003) Regulating general mutation rates: examination of the hypermutable state model for Cairnsian adaptive mutation. Genetics 163:1483-1496.
- Johnson KP, Seger J (2001) Elevated rates of nonsynonymous substitution in island birds. Mol Biol Evol 18:874-881.
- Branscomb A, Seger J, White RL (2000) Evolution of odorant receptors expressed in mammalian testes. Genetics 156:785-797.
- Herrick G, Seger J (1999) Imprinting and paternal genome elimination in insects. In Genomic Imprinting: An Interdisciplinary Approach (Results and Problems in Cell Differentiation, vol. 25) (ed R Ohlsson) pp 41-71. Springer-Verlag.
- Biol 3410: Principles of Ecology and Evolution
- Biol 3420: Evolutionary Biology
- Biol 5221: Human Evolutionary Genetics
- Biol 6092: Evolutionary Genetics and Genomics
- Biol 2005: Biology of Variation