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. 1977 May;86(1):175–185. doi: 10.1093/genetics/86.1.175

The Genetic Structure of Natural Populations of DROSOPHILA MELANOGASTER Xiii. Further Studies on Linkage Disequilibrium

Terumi Mukai 1, Robert A Voelker 1
PMCID: PMC1213663  PMID: 407125

Abstract

The Raleigh, North Carolina, population of Drosophila melanogaster was examined for linkage disequilibrium in 1974, several years after previous analyses in 1968, 1969, and 1970. αglycerol-3-phosphate dehydrogenase-1 (αGpdh-1), malate dehydrogenase-1 (Mdh-1), alcohol dehydrogenase (Adh), and hexokinase-C (Hex-C, tentative name, F. M. Johnson, unpublished; position determined by the present authors to be 2–74.5) were assayed for 617 second chromosomes, and esterase-C (Est-C) and octanol dehydrogenase (Odh) were assayed for 526 third chromosomes. In addition, two polymorphic inversions in the second chromosomes [In(2L)t and In(2R)NS] were examined, and the following findings were obtained: (1) No linkage disequilibrium between isozyme genes was detected. Significant linkage disequilibria were found only between the polymorphic inversions and isozyme genes [In(2L)t vs. Adh, and In(2R)NS vs. Hex-C]. Significant disequilibrium was not detected between In(2L)t and αGpdh-1, which is included in the inversion, but a tendency toward disequilibrium was consistently found from 1968 to 1974. The frequency of two-strand double crossovers within inversion In(2L)t involving a single crossover on each side of αGpdh-1 was estimated to be 0.00022. Thus, the consistent but not significant linkage disequilibrium between the two factors can be explained by recombination after the inversion occurred. (2) Previously existing linkage disequilibrium between Adh and In(2R)NS (the distance is about 30 cM, but the effective recombination value is about 1.75%) was found to have disappeared. (3) No higher-order linkage disequilibrium was detected. (4) Linkage disequilibrium between Odh and Est-C (the distance of which was estimated to be 0.0058 ± 0.002) could not be detected (χ2df=1 = 0.9).—From the above results, it was concluded that linkage disequilibria among isozyme genes are very rare in D. melanogaster, so that the Franklin-Lewontin model (Franklin and Lewontin 1970) is not applicable to these genes. The linkage disequilibria between some isozyme genes and polymorphic inversions may be explained by founder effect.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Langley C. H., Tobari Y. N., Kojima K. I. Linkage disequilibrium in natural populations of Drosophila melanogaster. Genetics. 1974 Nov;78(3):921–936. doi: 10.1093/genetics/78.3.921. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Lewontin R. C., Hubby J. L. A molecular approach to the study of genic heterozygosity in natural populations. II. Amount of variation and degree of heterozygosity in natural populations of Drosophila pseudoobscura. Genetics. 1966 Aug;54(2):595–609. doi: 10.1093/genetics/54.2.595. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Mukai T., Mettler L. E., Chigusa S. I. Linkage disequilibrium in a local population of Drosophila melanogaster. Proc Natl Acad Sci U S A. 1971 May;68(5):1065–1069. doi: 10.1073/pnas.68.5.1065. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Mukai T., Yamaguchi O. The genetic structure of natural populations of Drosophila melanogaster. XI. Genetic variability in a local population. Genetics. 1974 Feb;76(2):339–366. doi: 10.1093/genetics/76.2.339. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Muki T., Watanabe T. K., Yamaguchi O. The genetic structure of natural populations of Drosophila melanogaster. XII. Linkage disequilibrium in a large local population. Genetics. 1974 Aug;77(4):771–793. doi: 10.1093/genetics/77.4.771. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Nei M., Li W. H. Probability of identical monomorphism in related species. Genet Res. 1975 Aug;26(1):31–43. doi: 10.1017/s0016672300015822. [DOI] [PubMed] [Google Scholar]
  7. Nei M. The frequency distribution of lethal chromosomes in finite populations. Proc Natl Acad Sci U S A. 1968 Jun;60(2):517–524. doi: 10.1073/pnas.60.2.517. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Prakash S., Lewontin R. C. A molecular approach to the study of genic heterozygosity in natural populations. 3. Direct evidence of coadaptation in gene arrangements of Drosophila. Proc Natl Acad Sci U S A. 1968 Feb;59(2):398–405. doi: 10.1073/pnas.59.2.398. [DOI] [PMC free article] [PubMed] [Google Scholar]

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