Análise citogenética de Leontopithecus rosalia (Platyrrhini, Primates)

Abstract

There are currently three accepted monophyletic clades of Platyrrhini, based on molecular data: Cebidae, Atelidae and Pitheciidae. Cebidae has three subfamilies: Callitrichinae, Aotinae, and Cebinae. The smallest primates belong to the Callitrichinae subfamily and are included into the genera: Callithrix, Cebuella, Mico, Saguinus, Leontopithecus, and Callimico. Four species of the genus Leontopithecus Lesson, 1840, known as lion tamarins, are currently recognized: Leontopithecus rosalia (golden lion tamarin), L. chrysomelas (golden headed tamarin), L. chrysopygus (black lion tamarin) and L. caissara (black headed lion tamarin). These four species had their karyotypes described and presented the same diploid number (2n=46) and a karyotype that seemed conserved, even after the analysis of the GTG-banding patterns. Molecular cytogenetics analyses, including chromosome painting, have only been peformed on L. chrysomelas. We karyotypically analyzed three specimens of Leontopithecus rosalia (2n=46 and FN=74), including their GTG- and CBG- banding patterns, which were compared to published data. Chromosome painting with human chromosome-specific probes was performed in L. rosalia and the results were compared to those described for other Platyrrhini. FISH with telomeric and alpha-satellite DNA probes did not produce interstitial signals that could suggest chromosome rearrangements. The comparison of the karyotypes of L. rosalia and L. chrysomelas showed conservation during their speciation. Nevertheless, our chromosome painting results evidenced differences between the heterochromatic regions of both species, suggesting that the analysis of their repetitive sequences may yield data that will allow to differentiate their genomes.