Construction of a high density genetic map and QTL analysis of morphological traits in Aral barbel LucioBarbus brachycephalus (Teleost: Cyprinidae)

The cyprinid Aral barbel L. brachycephalus is endemic to the Aral Sea of Uzbekistan and was introduced in China in 2003. With increased cultivation, there is a need for more effective breeding strategies. We sequenced 146 individuals from a full-sib family and obtained 66,771 single nucleotide polymorphisms (SNPs) using specific locus amplified fragment sequencing (SLAF-seq). Among these, 31,019 SNPs were assigned to 50 linkage groups. The linkage map contained 4304 unique loci and spanned 2419.2 cM in total, with an average length of 48.4 cM. The length for each linkage group ranged from 5.2 cM to 76.2 cM, with an average distance of 0.4 cM to 0.8 cM. Using the linkage map, 72 QTL regions were predicted to be significantly associated with three breeding-related traits: body height (BH), total length (TL), and head breadth (HB). This study provides useful tools for the molecular mark-assisted breeding of L. brachycephalus.