Whole genome sequencing of experimental hybrids supports meiosis-like sexual recombination in Leishmania

• DOI: 10.1371/journal.pgen.1008042
• Publication Date: 2019-05-15T17:28:02Z
• Authors: Ehud Inbar; Jahangheer Shaik; Stefano A. Iantorno; Audrey Romano; Chukwunonso O. Nzelu; Katherine Owens; Mandy J. Sanders; Deborah Dobson; James A. Cotton; Michael E. Grigg; Stephen M. Beverley; David Sacks
• Keywords: Mendelian inheritance; Outcrossing

Hybrid genotypes have been repeatedly described among natural isolates of Leishmania, and the recovery experimental hybrids from sand flies co-infected with different strains or species Leishmania has formally demonstrated that members genus possess machinery for genetic exchange. As neither gamete stages nor cell fusion events directly observed during parasite development in vector, we relied on a classical analysis to determine if true sexual cycle. Here, used whole genome sequencing follow chromosomal inheritance patterns generated within between L. major infantum. We also sequenced first tropica. found each case parental somy allele contributions matched expected under meiosis 97–99% time. The were equivalent F1 progeny, heterozygous throughout most markers homozygous parents. Rare, non-Mendelian observed, including gain loss somy, heterozygosity, likely arose mitotic divisions progeny clones fly culture. While interspecies appeared be sterile, intraspecies able produce backcross outcross progeny. Analysis 5 an hybrid, as well 17 backcrosses involving hybrid tropica, revealed wide recombination, demonstrating crossing over occurs at meiosis, allowed us construct physical maps Leishmania. Altogether, findings provide strong evidence meiosis-like recombination presenting clear opportunities forward positional cloning important genes.