Data from: Genetic architecture of the variation in male-specific ossified processes on the anal fins of Japanese medaka
Kawajiri, Maiko et al. (2016), Data from: Genetic architecture of the variation in male-specific ossified processes on the anal fins of Japanese medaka, Dryad, Dataset, https://doi.org/10.5061/dryad.5v71p
Traits involved in reproduction evolve rapidly and show great diversity among closely related species. However, the genetic mechanisms that underlie the diversification of courtship traits are mostly unknown. Japanese medaka fishes (Oryzias latipes) use anal fins to attract females and to grasp females during courtship; the males have longer anal fins with male-specific ossified papillary processes on the fin rays. However, anal fin morphology varies between populations: the southern populations tend to have longer anal fins and more processes than the northern populations. In the present study, we conducted quantitative trait locus (QTL) mapping to investigate the genetic architecture underlying the variation in the number of papillary processes of Japanese medaka fish and compared the QTLs with previously identified QTLs controlling anal fin length. First, we found that only a few QTLs were shared between anal fin length and papillary process number. Second, we found that the numbers of papillary processes on different fin rays were often controlled by different QTLs. Finally, we produced another independent cross and found that some QTLs were repeatable between the two crosses, whereas others were specific to only one cross. These results suggest that variation in the number of papillary processes is polygenic and controlled by QTLs that are distinct from those controlling anal fin length. Thus, different courtship traits in Japanese medaka share a small number of QTLs and have the potential for independent evolution.