Identifying a major QTL associated with salinity tolerance in Nile tilapia using QTL-seq sequencing

By using QTL-seq sequencing strategy, a QTL study on salt tolerant traits firstly identified two significant QTL intervals (chrLG4 and chrLG18) in the Nile tilapia. Fine mapping with microsatellite or SNP markers suggested a major QTL region was located at 23.0 Mb of chrLG18 with a % explained phenotypic variation of 79% and a LOD value of 95. Our findings suggest that QTL-seq can be effectively utilized in QTL mapping of salt tolerant traits in fish. The identified major QTL is a promising locus to improve our knowledge on genetic mechanism of salt tolerance in tilapia.