Abstract
The dynamics of allelic frequencies at a single multiallelic locus under gene conversion is studied. Generations are discrete and nonoverlapping; the diploid monoecious population mates at random; selection, mutation, and random drift are negligible. Analytical and numerical investigation indicates the following. (i) If gene conversion is biased within at least one pair of alleles, then the frequency of at least one allele must become arbitrarily small. (ii) If conversion is biased within every pair of alleles, then the frequency of at most one allele can fail to become arbitrarily small. Although allelic frequencies may become repeatedly small instead of remaining small, the biological ubiquity of small random perturbations (due, e.g., to random genetic drift) guarantees the ultimate loss of at least one allele in case i and of all alleles but one in case ii. The decay of genetic variability is often sufficiently rapid to imply that biased gene conversion can be an important mechanism for the genetic divergence of isolated populations.
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- Fogel S., Mortimer R. K. Informational transfer in meiotic gene conversion. Proc Natl Acad Sci U S A. 1969 Jan;62(1):96–103. doi: 10.1073/pnas.62.1.96. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gutz H., Leslie J. F. Gene conversion: a hitherto overlooked parameter in population genetics. Genetics. 1976 Aug;83(4):861–866. doi: 10.1093/genetics/83.4.861. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hilliker A. J., Chovnick A. Further observations on intragenic recombination in Drosophila melanogaster. Genet Res. 1981 Dec;38(3):281–296. doi: 10.1017/s0016672300020619. [DOI] [PubMed] [Google Scholar]
- Leblon G., Rossignol J. L. Mechanism of gene conversion in Ascobolus immersus. 3. The interaction of heteroallelas in the conversion process. Mol Gen Genet. 1973 Apr 12;122(2):165–182. doi: 10.1007/BF00435189. [DOI] [PubMed] [Google Scholar]
- Nagylaki T., Crow J. F. Continuous selective models. Theor Popul Biol. 1974 Apr;5(2):257–283. doi: 10.1016/0040-5809(74)90045-8. [DOI] [PubMed] [Google Scholar]
- Nagylaki T., Petes T. D. Intrachromosomal gene conversion and the maintenance of sequence homogeneity among repeated genes. Genetics. 1982 Feb;100(2):315–337. doi: 10.1093/genetics/100.2.315. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nelson O. E. The Waxy Locus in Maize III. Effect of Structural Heterozygosity on Intragenic Recombination and Flanking Marker Assortment. Genetics. 1975 Jan;79(1):31–44. doi: 10.1093/genetics/79.1.31. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ohta T. Allelic and nonallelic homology of a supergene family. Proc Natl Acad Sci U S A. 1982 May;79(10):3251–3254. doi: 10.1073/pnas.79.10.3251. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ohta T. On the evolution of multigene families. Theor Popul Biol. 1983 Apr;23(2):216–240. doi: 10.1016/0040-5809(83)90015-1. [DOI] [PubMed] [Google Scholar]
- PROUT T. Some effects of variations in the segregation ratio and of selection on the frequency of alleles under random mating. Acta Genet Stat Med. 1953;4(2-3):148–151. [PubMed] [Google Scholar]