Revisiting the Karyotype Evolution of Neotropical Boid Snakes: A Puzzle Mediated by Chromosomal Fissions
Patrik F. Viana,
Tariq Ezaz,
Marcelo de Bello Cioffi,
Thomas Liehr,
Ahmed Al-Rikabi,
Rodrigo Tavares-Pinheiro,
Luiz Antônio Carlos Bertollo,
Eliana Feldberg
Affiliations
Patrik F. Viana
Laboratory of Animal Genetics, Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Av. André Araújo 2936, Petrópolis, Manaus 69067-375, AM, Brazil
Tariq Ezaz
Institute for Applied Ecology, Faculty of Science and Technology, University of Canberra, Canberra 12 2616, ACT, Australia
Marcelo de Bello Cioffi
Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-090, SP, Brazil
Thomas Liehr
Institute of Human Genetics, University Hospital Jena, Am Klinikum 1, 07747 Jena, Germany
Ahmed Al-Rikabi
Institute of Human Genetics, University Hospital Jena, Am Klinikum 1, 07747 Jena, Germany
Rodrigo Tavares-Pinheiro
Departamento de Ciências Biológicas e da Saúde, Laboratório de Herpetologia, Universidade Federal do Amapá, Macapá 68903-419, AP, Brazil
Luiz Antônio Carlos Bertollo
Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos 13565-090, SP, Brazil
Eliana Feldberg
Laboratory of Animal Genetics, Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Av. André Araújo 2936, Petrópolis, Manaus 69067-375, AM, Brazil
The Boidae family is an ancient group of snakes widely distributed across the Neotropical region, where several biogeographic events contributed towards shaping their evolution and diversification. Most species of this family have a diploid number composed of 2n = 36; however, among Booidea families, the Boidae stands out by presenting the greatest chromosomal diversity, with 2n ranging between 36 and 44 chromosomes and an undifferentiated XY sex chromosome system. Here, we applied a comparative chromosome analysis using cross-species chromosome paintings in five species representing four Boidae genera, to decipher the evolutionary dynamics of some chromosomes in these Neotropical snakes. Our study included all diploid numbers (2n = 36, 40, and 44) known for this family and our comparative chromosomal mappings point to a strong evolutionary relationship among the genera Boa, Corallus, Eunectes, and Epicrates. The results also allowed us to propose the cytogenomic diversification that had occurred in this family: a process mediated by centric fissions, including fission events of the putative and undifferentiated XY sex chromosome system in the 2n = 44 karyotype, which is critical in solving the puzzle of the karyotype evolution of boid snakes.
