fshr: a fish sex-determining locus shows variable incomplete penetrance across flathead grey mullet populations

• Main Authors: Serena Ferraresso, Luca Bargelloni, Massimiliano Babbucci, Rita Cannas, Maria Cristina Follesa, Laura Carugati, Riccardo Melis, Angelo Cau, Manos Koutrakis, Argyrios Sapounidis, Donatella Crosetti, Tomaso Patarnello
• Format: Article
• Language: English
• Published: Elsevier 2021-01-01
• Series: iScience
• Subjects: Genetics; Evolutionary Biology; Genomics
• Online Access: http://www.sciencedirect.com/science/article/pii/S258900422031083X

Summary: Whole-genome sequencing data were produced from a single flathead grey mullet female and assembled into a draft genome sequence, whereas publicly available sequence data were used to obtain a male draft sequence. Two pools, each consisting of 60 unrelated individuals, respectively, of male and female fish were analyzed using Pool-Sequencing. Mapping and analysis of Pool-Seq data against the draft genome(s) revealed >30 loci potentially associated with sex, the most promising locus of which, encoding the follicle-stimulating hormone receptor (fshr) and harboring two missense variants, was genotyped on 245 fish from four Mediterranean populations. Genotype data showed that fshr represents a previously unknown sex-determining locus, although the incomplete association pattern between fshr genotype and sex-phenotype, the variability of such pattern across different populations, and the presence of other candidate loci reveal that a greater complexity underlies sex determination in the flathead grey mullet.