Abstract
In order to detect sex-linked DNA markers, linkage analysis was performed in each of three ayu half-sib families using 32 amplified fragment length polymorphism primer combinations, four microsatellite DNA primer sets and phenotypic sex (male). In each family the sex-determining locus appeared in a distal position on one of the linkage groups in which the D7-141* marker was strongly associated with male gender. The D7-141* marker was amplified in all of the male ayu (100%), and 8.7% of the female ayu. The D7-141* marker was detected in all male ayu at a level similar to that in the 40 wild individuals. These results suggest that the D7-141* marker is a male-specific marker linked with the sex-determining locus of the male in amphidromous ayu.
