High-Resolution Recombination Maps in Drosophila melanogaster

Our lab characterized the products of 5,860 female meioses in Drosophila melanogaster by genotyping (whole-genome NGS) a total of 139 million informative SNPs and mapped 106,964 recombination events at a resolution down to 2 kilobases. This approach allowed us to generate CO maps and infer gene conversion (GC) maps across the genome with unprecedented high resolution.

CO rates vary significantly at the scale of 100-kb in a highly punctuated manner with hot- and coldspots within regions traditionally associated with non-reduced recombination. GC rates are more uniformly distributed than CO rates and are also detectable in regions with reduced or absent COs.

Because we analyzed the progeny of eight different crosses between natural strains of D. melanogaster, we were able to identify significant intra-specific variation in CO landscapes. Our results therefore emphasize the need for obtaining estimates of recombination based on multiple crosses and genotypes rather than on a single or two crosses, even if highly detailed in resolution.

Citation: Comeron JM, Ratnappan R, Bailin S (2012) The Many Landscapes of Recombination in Drosophila melanogaster. PLoS Genet 8(10): e1002905. https://doi.org/10.1371/journal.pgen.1002905

Download Table with Drosophila melanogaster 100-kb resolution CO maps (R5 and R6).

 

High-Resolution Recombination Map in Drosophila yakuba

Our lab applied a novel and highly efficient approach to generate whole-genome high-resolution crossover maps in D. yakuba. This approach involves crosses between multiple wild-type parental genotypes and, in turn, provides the opportunity to capture species-wide genetic maps that are more informative for genomic and evolutionary analyses than those generated using a single cross. Our crossing and genotyping schemes also reduced the potential effects of using inbred lines when studying meiotic outcomes. In all, we genotyped (whole-genome NGS) more than 1,600 individual meiotic events, allowing us to identify several key distinct properties relative to D. melanogaster.

Citation: Pettie N, Llopart A, Comeron JM (2022) Meiotic, genomic and evolutionary properties of crossover distribution in Drosophila yakuba. PLoS Genet 18(3): e1010087. https://doi.org/10.1371/journal.pgen.1010087