design: A PCR reaction was set with KAPA HiFi HotStart ReadyMix (Roche) to amplify 291 bp around the dsxF target using primers that contained Illumina Nextera Transposase adapters. In order to maintain the proportion of the reads corresponding to particular alleles at the target site, the PCR reactions were performed under non-saturating conditions and thus they were allowed to run for 20 cycles.The fragments were then purified using Wizard SV Gel and PCR Clean-Up System (Promega).