Abstract
The statistical properties of the process describing the genealogical history of a random sample of genes at a selectively neutral locus which is linked to a locus at which natural selection operates are investigated. It is found that the equations describing this process are simple modifications of the equations describing the process assuming that the two loci are completely linked. Thus, the statistical properties of the genealogical process for a random sample at a neutral locus linked to a locus with selection follow from the results obtained for the selected locus. Sequence data from the alcohol dehydrogenase (Adh) region of Drosophila melanogaster are examined and compared to predictions based on the theory. It is found that the spatial distribution of nucleotide differences between Fast and Slow alleles of Adh is very similar to the spatial distribution predicted if balancing selection operates to maintain the allozyme variation at the Adh locus. The spatial distribution of nucleotide differences between different Slow alleles of Adh do not match the predictions of this simple model very well.
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Selected References
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- Aquadro C. F., Desse S. F., Bland M. M., Langley C. H., Laurie-Ahlberg C. C. Molecular population genetics of the alcohol dehydrogenase gene region of Drosophila melanogaster. Genetics. 1986 Dec;114(4):1165–1190. doi: 10.1093/genetics/114.4.1165. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chovnick A., Gelbart W., McCarron M. Organization of the Rosy locus in Drosophila melanogaster. Cell. 1977 May;11(1):1–10. doi: 10.1016/0092-8674(77)90312-9. [DOI] [PubMed] [Google Scholar]
- Hudson R. R. Properties of a neutral allele model with intragenic recombination. Theor Popul Biol. 1983 Apr;23(2):183–201. doi: 10.1016/0040-5809(83)90013-8. [DOI] [PubMed] [Google Scholar]
- Kaplan N., Hudson R. R. The use of sample genealogies for studying a selectively neutral m-loci model with recombination. Theor Popul Biol. 1985 Dec;28(3):382–396. doi: 10.1016/0040-5809(85)90036-x. [DOI] [PubMed] [Google Scholar]
- Kreitman M. E., Aguadé M. Excess polymorphism at the Adh locus in Drosophila melanogaster. Genetics. 1986 Sep;114(1):93–110. doi: 10.1093/genetics/114.1.93. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Langley C. H., Montgomery E., Quattlebaum W. F. Restriction map variation in the Adh region of Drosophila. Proc Natl Acad Sci U S A. 1982 Sep;79(18):5631–5635. doi: 10.1073/pnas.79.18.5631. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Strobeck C. Expected linkage disequilibrium for a neutral locus linked to a chromosomal arrangement. Genetics. 1983 Mar;103(3):545–555. doi: 10.1093/genetics/103.3.545. [DOI] [PMC free article] [PubMed] [Google Scholar]