Evidence of gene conversion associated with a selective sweep in Drosophila melanogaster.
Since Drosophila melanogaster colonized Europe from tropical Africa 10 to 15 thousand years ago, it is expected that adaptation has played a major role in this species in recent times. A previously conducted multilocus scan of noncoding DNA sequences on the X chromosome in an ancestral and a derived population of D. melanogaster revealed that some loci have been affected by directional selection in the European population. We investigated if the pattern of DNA sequence polymorphism in a region surrounding one of these loci can be explained by a hitchhiking event. We found strong evidence that the studied region around the gene unc-119 was shaped by a recent selective sweep, including a valley of reduced heterozygosity of 83.4 kb, a skew in the frequency spectrum, and significant linkage disequilibrium on one side of the valley. This region, however, was interrupted by gene conversion events leading to a strong haplotype structure in the center of the valley of reduced variation.
Glinka
Sascha
S
Section of Evolutionary Biology, Department of Biology II, Ludwig-Maximilians University, Planegg-Martinsried, Germany. glinka@zi.biologie.uni-muenchen.de
De Lorenzo
David
D
Stephan
Wolfgang
W
D000349:Africa; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D005060:Europe; D019143:Evolution, Molecular; D005785:Gene Conversion; D017344:Genes, Insect; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D015810:Linkage Disequilibrium; D008957:Models, Genetic; D009154:Mutation; D012641:Selection, Genetic; D016415:Sequence Alignment; D014960:X Chromosome / Q000235:genetics
D004247:DNA