Genetic map construction and quantitative trait locus (QTL) analysis on growth-related traits in common carp (Cyprinus carpio L.)

Abstract

Common carp (Cyprinus carpio L.) is one of the most widely distributed freshwater species in the world with important values in aquaculture, however, its quantitative trait loci (QTLs) associated to growth-related traits have been rarely identified. In this study, using F2 populations derived from a cross between Purse red common carp (C. carpio var. wuyuanensis) and Xingguo red common carp (C. carpio var.singuonensis), a genetic linkage map of common carp based on amplified fragment length polymorphisms (AFLP) and microsatellite (SSR) markers was constructed, meanwhile QTL analysis were conducted for growth-related traits. A total of 347 AFLP and 22 SSR markers were assembled on the map, which comprised 50 linkage groups and covered 5608.1cM Kosambi. A total of 25 QTLs were identified for growth-related traits, including four QTLs for body weight, one QTL for total length, four QTLs for standard length, six QTLs for body height, eight QTLs for caudal peduncle length and two QTLs for caudal peduncle height, which explained 0.05 to 61.40% of phenotypic variation. Meanwhile, comparison of linkage maps between common carp and zebrafish was also conducted, providing a new insight into the genetic base of the QTL affecting the growth-related traits. This study will be useful for conducting marker-assisted selection (MAS) breeding programs in common carp. Key words: Cyprinus carpio, F2 populations, amplified fragment length polymorphisms, microsatellite, quantitative traits locus.