INVESTIGADORES
GIMENEZ mabel dionisia
artículos
Título:
Molecular analysis of populations of Ctenomys (Caviomorpha, Rodentia) with high karyotypic variability
Autor/es:
M.D. GIM√ČNEZ; P.M. MIROL; C.J. BIDAU; J.B. SEARLE
Revista:
CYTOGENETIC AND GENOME RESEARCH
Editorial:
KARGER
Referencias:
Lugar: Basel; Año: 2002 vol. 96 p. 130 - 136
ISSN:
1424-8581
Resumen:
The tuco-tucos (Ctenomys) are South American subterranean rodents that are some of the most chromosomally variable of all mammals. In this study we focus on Ctenomys of the "Corrientes species group" from that Argentine province and consisting of C dorbignyi, C. perrensi, C. roigi and unnamed populations (Ctenomys sp.). A diploid range of 41-70 has been demonstrated for these taxa with multiple Robertsonian changes, pericentric inversions, heterochromatic modifications and other chromosomal rearrangements. To analyse the molecular variation in the Corrientes group, a 402 base pair fragment of mitochondrial cytochrome b was sequenced in 75 individuals from 26 populations. This generated 15 different haplotypes which were subjected to phylogenetic analysis. The different species within the Corrientes group failed to form monophyletic groups in the phylogenetic trees we generated and the divergences between haplotypes were low. Therefore, these molecular data demonstrate the recent subdivision of the Corrientes group with a substantial accumulation of chromosomal differences. Through our new chromosomal data and cytochrome b studies, we are able to subdivide the Ctenomys sp. populations into two groups and hypothesize on their relationships with the described Corrientes group species. Further studies are needed to establish the basis of the phenomenal chromosomal variation in this group.