The genetic basis of scale-loss phenotype in the rapid radiation of Takifugu fishes

The genetic basis of scale-loss in Takifugu pufferfishes

 Abstract

Rapid radiation associated with phenotypic divergence and convergence provides an opportunity to study the genetic mechanisms of evolution. Here we investigate the genus Takifugu that has undergone explosive radiation relatively recently and contains a subset of closely-related species with a scale-loss phenotype. By using observations during development and genetic mapping approaches, we show that the scale-loss phenotype of two Takifugu species, T. pardalis Temminck & Schlegel and T. snyderi Abe, is largely controlled by an overlapping genomic segment (QTL). A search for candidate genes underlying the scale-loss phenotype revealed that the QTL region contains no known genes responsible for the evolution of scale-loss phenotype in other fishes. These results suggest that the genes used for the scale-loss phenotypes in the two Takifugu are likely the same, but the genes used for the similar phenotype in Taki...