The brown brocket deer (Mazama gouazoubira) is the most common deer in Brazil, presenting great ecological plasticity and being distributed in different brazilian biomes. Displays intraspecific variation in chromosome number, which is occasioned by the occurrence of Robertsonian translocations and the presence of B chromosomes. This chromosomal variation, also known as chromosomal polymorphism may be originated by the presence of fragile sites, which explains the large karyotypic variation found in the genus Mazama. Because no cytogenetic study of this specie identified chromosomes involved in Robertsonian translocations, it is unclear whether these chromosomes are the same in animals originating from different regions of Brazil. Currently, despite the origin of B chromosomes is still uncertain, it has been suggested that they may have derived from the set of A chromosomes, but no study of this issue was conducted with this specie. Thus, it became important to evaluate cytogenetically specimens of M. gouazoubira from different regions of Brazil, with the aim of identifying individuals variants (carriers of Robertsonian translocation and B chromosomes), the translocated chromosomes (relating these chromosomes with the region of origin of the animals) and the origin of B chromosomes, also determine if the fragile sites produced by aphidicolin are linked to the chromosomes involved in the polymorphism presented by this specie. For this, blood and skin samples of 116 animals from different regions of the country will be analyzed. Through conventional staining (Giemsa) will be detected which animals are carriers of chromosome translocations and B chromosomes. With the aid of the G-banding and chromosome painting, it will be possible identify the translocated chromosomes and the chromosomes that originated the B chromosomes. Aphidicolin is used to induce breaks at fragile sites, whereas the involved chromosomes are detected by chromosome painting and G-banding. Thus, it is expected to obtain a profile of chromosomal rearrangements that occur in this specie, in order to understand the process of chromosomal evolution that is so important in speciation of the genus Mazama.
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