In Silico Chromosome Mapping of the Male-Specific/Linked Loci in the Jade Perch (Scortum barcoo) Suggests Chromosome 19 as the Putative Y Sex Chromosome

Jade perch (Scortum barcoo) has an XX/XY sex-determination system (SDS); however, its sex chromosomes and sex-determining region remain unknown. The recent availability of the jade perch chromosome-level genomic data provides a valuable resource for pinpointing the location of functional genes and the whole genomic structure. In this study, we conducted. In silico chromosome mapping of male-specific/linked loci of jade perch and identified a potential 11.18 Mb male-linked region localized on chromosome 19 (SBA19). Repeat annotations of the male-linked region revealed an abundance of transposable elements, particularly Ty3/Gypsy and novel repeats. Sequence analysis of this region identified a remnant of amh gene, which is considered a potential candidate for SDS in many teleosts. A duplicate copy of amh remnant was located at SBA6. These duplicated amh copies were highly similar to those of XX/XY SDS in teleosts, in which one copy of amh was identified on the Y sex chromosome. Taken all together, we hypothesize SBA19 as the putative sex chromosome and the 11.18 Mb male-linked region to be a potential male-determining region.