Isolation of the male-specific genetic marker in gibel carp. (A) BSA of the male pools and female pools. Lines 1, 2, and 3 indicate male pools (♂), while lines 4, 5, and 6 indicate female pools (♀). Primer combinations from left to right are: E10/M16, E10/M15, E10/M14, E15/M7, E15/M6, and E15/M5. The black box shows the differentially-amplified fragment between females and males. (B) Individual screening of 15 females and 15 males using the primer combination of E15/M5. The arrow indicates the male-specific AFLP fragment. (C) PCR detection analysis of the male-specific SCAR marker in the 19 randomly-picked males and the 19 randomly-picked females in the offspring, as well as of the parental individuals. ♀, female; ♂, male; M♀, maternal fish from strain DA; P♂, paternal fish from strain A.