title: Absence of linkage disequilibria between chromosomal arrangements and mtDNA haplotypes in natural populations of Drosophila subobscura from the Balkan Peninsula.
abstract: The genetic structure of Drosophila subobscura from the Balkan Peninsula was studied with respect to restriction site polymorphism of mitochondrial DNA in populations from the Derventa River Gorge and Sicevo Gorge (Serbia). To investigate the role of cytonuclear interactions in shaping mitochondrial DNA variability in natural populations of this species, the study was complemented with the analysis of linkage disequilibria between mitochondrial haplotypes and chromosomal inversion arrangements. Similar to other populations of D. subobscura, two main haplotypes (I and II) were found, as well as a series of less common ones. The frequencies of haplotypes I and II accounted for 25.8% and 71.0%, respectively, in the population from the Derventa River Gorge, and for 32.4% and 58.1%, respectively, in the population from Sicevo Gorge. One of the haplotypes harbored a large insertion (2.7 kb) in the A+T rich region. The frequency distribution of both haplotypes did not depart from neutrality. Contrary to prior studies, we did not detect any significant linkage disequilibrium between the two most frequent mtDNA haplotypes and any of the chromosomal arrangements in either of the populations. We conclude that linkage disequilibrium is not a general occurrence in natural populations of D. subobscura, and we discuss how transient coadaptations, ecologically specific selective pressures, and demographics could contribute to population-specific patterns of linkage disequilibrium.
authors.affiliation: Faculty of Biology, University of Belgrade, Studentski trg 3, 11000 Belgrade, Serbia. mihailoj@bio.bg.ac.rs
authors.forename: Mihailo
authors.initials: M
authors.lastname: Jelić
authors.forename: José A
authors.initials: JA
authors.lastname: Castro
authors.forename: Zorana
authors.initials: Z
authors.lastname: Kurbalija Novičić
authors.forename: Bojan
authors.initials: B
authors.lastname: Kenig
authors.forename: Danica
authors.initials: D
authors.lastname: Dimitrijević
authors.forename: Marija
authors.initials: M
authors.lastname: Savić Veselinović
authors.forename: Miloš
authors.initials: M
authors.lastname: Jovanović
authors.forename: Dragomir
authors.initials: D
authors.lastname: Milovanović
authors.forename: Marina
authors.initials: M
authors.lastname: Stamenković-Radak
authors.forename: Marko
authors.initials: M
authors.lastname: Andjelković
mesh_terms: D000818:Animals; D002875:Chromosomes / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D004330:Drosophila / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics*; D015810:Linkage Disequilibrium; D015183:Restriction Mapping; D055771:Serbia; D020577:Wolbachia / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial