Drosophila mauritiana DNA-Sequencing

We generated a SNP based crossover map for Drosophila mauritiana utilizing low-coverage whole genome sequencing for relatively low cost. We analyzed crossing over in 105 progeny produced by heterozygous females created by crossing different isolates of D. mauritiana. This analysis allowed us to position 327 crossover events derived from 105 single meioses and identify them as single, double, or triple crossover chromatids. Our data confirm previously published work that the crossover frequency in D. mauritiana is higher than that of D. melanogaster. However, our analysis shows much of the observed difference is due to increases on crossing over on specific chromosome arms rather than a global increase genome wide. We generated a new Maximum Likelihood Estimation tool for obtaining Weinstein tetrad distributions for exchange on each arm and a simplified algorithm for assessing crossover interference. We use these tools to compare crossover number and distribution between D. melanogaster, D. yakuba, and D. mauritiana.