Genetics and Molecular Biology
On-line version ISSN 1678-4685
LOURENCO, Luciana Bolsoni; RECCO-PIMENTEL, Shirlei M. and CARDOSO, Adão José. A second case of multivalent meiotic configurations in diploid species of Anura. Genet. Mol. Biol. [online]. 2000, vol.23, n.1, pp. 131-133. ISSN 1678-4685. http://dx.doi.org/10.1590/S1415-47572000000100024.
We analyzed the meiotic chromosomes of specimens from the two karyological groups of Physalaemus petersi (Jiménez de la Espada, 1872) described in the literature. Multivalent configurations (rings or chains) were observed in both groups. This meiotic organization resulted from the terminal association of non-homologous chromosomes, and an analysis of C-banded multivalents indicated no involvement of heterochromatic regions in these associations. A possible explanation for such meiotic configurations is the occurrence of heterozygous translocations. Thus, multivalents may indicate the involvement of translocation events in the karyotypic evolution of P. petersi.