Cytogenetic and molecular analysis of Veado-roxo (Mazama nemorivaga) in Brazil

• Grant number: 22/14370-3
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): June 01, 2023
• Status: Discontinued
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: José Maurício Barbanti Duarte
• Grantee: Raquel Muhlbeier Bonato
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated research grant: 17/07014-8 - The use of actual topotypes to produce genotypes and cytotypes in the taxonomic review of the Mazama genus: the basis for the species conservation, AP.BTA.TEM
• Associated scholarship(s): 24/06211-8 - Comparative Study of B Chromosomes in Neotropical Deer, BE.EP.MS

Abstract

The Cervidae family is the second most diverse of the Artiodactyla order, and its great variation makes it difficult to understand the evolutionary history and taxonomic classification of its species. Neotropical deer of the genus Mazama are distinguished by an expressive chromosomal polymorphism and a high morphological convergence, reasons for confusion in the classification and delimitation of the species. Phylogenetic analyses by mitochondrial DNA (Cytb and COI genes) of the species M. nemorivaga Cuvier 1817 demonstrate a structure of the species in three clades, with high statistical support and strong geographic correlation. Together, cytogenetic studies have shown variations from 2n = 67 - 69, NF = 69 - 72, multiple B chromosomes, and a single sexual system in some individuals and multiple in others, which centric fusions and X-autosomal fusion can explain. This chromosomal variation and the evidence of the clades lead to the hypothesis that the Amazon River acts as a geographic barrier between the populations of M. nemorivaga and that there may be reproductive isolation between them. In this context, molecular cytogenetics becomes essential to reveal the real chromosomal differences and help to understand the taxonomic relationships between the different populations of M. nemorivaga. In this project, 12 specimens stored in the cell bank of the Deer Research and Conservation Center (NUPECCE) will be evaluated, using BAC probes already mapped on the chromosomes of Subulo gouazoubira, a species that retained the ancestral karyotype of Cervidae. Fragments of the mitochondrial genes Cytochrome B (CytB), Dehydrogenase subunit 5 (ND5) and Control region (D-Loop) will also be amplified and sequenced, and genetic distance analyses, haplotype network construction and genetic structuring, in order to verify whether there is a correlation between chromosomal changes and genetic distance. Based on cytogenetic and molecular analysis, the hypothesis that M. nemorivaga constitutes a complex of cryptic species will be tested.