Functional Genomic Analysis of Sex Determination and Differentiation in Teleost Fish

Abstract

In many aquacultured fish species, the production of monosex stocks is highly desirable because usually one sex grows more than the other or produces valuable gametes (e.g., caviar). The sex ratio of a population depends largely on the combined result of the processes of sex determination and differentiation. Fish exhibit a great diversity of sex-determining (SD) mechanisms, and sex differentiation involves the expression of a considerable number of genes in a spatial and temporal order. For genetic selection programs and monosex production in aquaculture, knowing these complex processes is essential. Functional genomics involving the application of microarrays, next-generation sequencing, and other functional genomic approaches, as well as epigenetics, can play an increasingly relevant role in deciphering relevant genes and signaling pathways and how these can be influenced by the environment. Here, we present this chapter on sex determination and differentiation in fish and review the advances made to date using functional genomic analysis using various experimental approaches. We also illustrate some technical complications involving changes in gene expression and DNA methylation. Finally, we suggest some avenues for further research in both model fish species and fish species facing specific problems within an aquaculture context. © 2012 John Wiley & Sons, Inc.