part of determination of imaginal disc primordium genital disc development determination of genital disc primordium Allocation of embryonic cells to the genital imaginal disc founder populations. Early in development at the blastoderm stage, the anlage of the genital disc of both sexes consists of three primordia: the female genital primoridum lcoated anteriorly, the anal primoridum located posteriorly, and the male gential primordium between the two. GO:0035225 biological_process