Detección de marcadores ligados al sexo en Gambusia a partir de A RAD-seq

Abstract

The obtaining of representative genes of the sex determination in fish remains nowadays a little-known aspect, to a large extent by the various chromosomal systems within a same genus and even species. Gambusia holbrooki is a fish of the poeciliids’ family, ecologically interesting as one of the most invasive species in the word. The present work intends to find a molecular marker to distinguish the sex of Gambusia holbrooki, and in order to provide new knowledge on the sex determination in fish. To this end, the RAD-seq (restriction site-associated DNA sequencing) technique was used to identify thousands of genetic markers (RAD-tags) with variations in single nucleotides (SNPs) between males and females. From 44271 RAD-tags available in the STACKS database, the search for loci exclusive of a sex and loci with a differential pattern of SNPs was carried out among males and females of Gambusia holbrooki. For the detection of these differentiating RAD-tag loci, various bioinformatic programs based on the FST statistic were used, as well as a subsequent functional analysis of the possible candidate genes. Both searches concluded that none of the RAD-tags loci of the study was specific to differentiate between males and females of the species Gambusia holbrooki