The identification of genes involved in the evolution of color patterns in fish

The genetic basis of morphological variation, both within and between species, provides a major topic in evolutionary biology. Teleost fish produce most elaborate color patterns, and among the more than 20 000 species a number have been chosen for more detailed analyses because they are suitable to study particular aspects of color pattern evolution. In several fish species, color variants and pattern variants have been collected, transcriptome analyses have been carried out, and the recent advent of gene editing tools, such as CRISPR/Cas9, has allowed the production of mutants. Covering mostly the literature from the last three years, we discuss the cellular basis of coloration and the identification of loci involved in color pattern differences between sister species in cichlids and Danio species, in which cis-regulatory changes seem to prevail.