Cromossomos sexuais de anuros: o estado da arte

• Autor(a) principal: Oliveira, Hudiny Allan de
• Data de Publicação: 2022
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/216371
• topic: Sex chromosomes; Amphibians; Determination of sex; Genetic systems; Cromossomos sexuais; Anuros; Anfíbios; Determinação do sexo; Sistemas genéticos

Sex determination in vertebrates can occur through different mechanisms and a variety of genetic systems. The most common mechanisms involve gene sex determination (GSD) and environmental sex determination (ESD). Some groups of vertebrates can use both mechanisms between their species, or even within the same species, as observed in reptiles. There are two systems found in abundance known as the XY and ZW systems in vertebrates that use genetic determination. These genetic systems are known as XY for mammals and as ZW for birds and snakes, however other vertebrates have a miscellany of these two systems and other less usual ones, such as fish and anurans. Most anurans have homomorphic sex chromosomes in the XY system, which could indicate the recent age of these chromosomes. The present study carried out a revision about the sex chromosomes of anurans, due to the little existing knowledge in literature. Additionally, to the usual XY and ZW systems, there are anurans species with both chromosome systems in the same individual; anurans with multiple sex chromosomes and several candidate genes for sex determinants. It is still unclear why most karyotyped anurans have homomorphic sex chromosomes. Moreover, two non-exclusive mechanisms have been proposed to maintain this morphology: turnover and the fountain of youth.