Candidate growth genes in finfish - Where should we be looking?

On the back of the genomics revolution significant investment has been made towards the identification of candidate growth genes in livestock that can be used to speed up genetic gains through marker-assisted selection. Many putative candidate genes so far identified are situated within important growth-related pathways that also are known to influence somatic growth in finfish. In particular, there has been intense research focus on genes within the somatotropic axis and myogenic transforming growth factor superfamily. For many of these genes, significant associations have been found between gene polymorphisms and phenotypic growth rate. Due to likely conservation of gene function within growth pathways in vertebrates, finfish aquaculture can streamline the initial process of identifying growth genes by taking advantage of the vast repository of information available on how certain genes in terrestrial vertebrates influence growth rate. In an effort to stimulate increased researcher focus into the identification of fish growth genes, we review the terrestrial livestock and finfish literature, and based on positive associations between genes and growth, identify those genes that should be further targeted as candidate growth genes in aquaculture species.