ISSN: 2642-1194
Authors: Daniel SN*, Goes CAG, Foresti FP and Foresti F
The Astyanax genus is composed of approximately 154 species, abundant in most of the Brazilian watersheds. In this sense, studies have revealed the presence of B chromosomes in populations of at least 12 species, which have different number, shape and size. B chromosomes are defined as additional elements, with particular evolution, transmission and maintenance, in addition to not following the Mendelian transmission laws. Thus, species of the Astyanax genus are presented as excellent models of evolutionary studies, maintenance and behavior of B chromosomes in fish; however, this information in this genre is often disconnected. In addition, several B-specific probes were isolated from B chromosomes of fish over the last decade, which together with genomic sequencing, have allowed for very detailed analyzes and results on its molecular structure. However for the Astyanax group there is no bibliographic survey relating the species or the populations carrying B chromosomes, nor the described morphologies, heterochromatic pattern, mitotic behavior, gene mapping, presence of functional genes, among others. Thus, this review compiles information aimed at the knowledge of supernumeraries in neotropical fish, more specifically those that comprise the genus Astyanax.
Keywords: B Chromosomes; Mitotic Instability; Morphotypes; Neotropical Fish; Supernumerary Chromosomes
