Phylogenetic relationships among Robertsonian karyomorphs of Graomys griseoflavus (Rodentia, Muridae) by mitochondrial DNA sequencing

CATANESI C. I.; VIDAL RIOJA L. A.; CRISCI J. V.; ZAMBELLI A. D.

HEREDITAS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2002 vol. 136 p. 130 - 136

0018-0661

Graomys griseoflaus (Waterhouse 1837) is a phyllotine murid rodent with a Robertsonian autosomal polymorphism, having been described 2n=42, 41, 38, 37, 36, 35 and 34 karyomorphs, and proposed a chromosomal divergence pathway accounted by four sequential Robertsonian fusions.Sequences of a fragment (422 bp long) of the cytochrome b (cyt b) mitochondrial gene and its 5 flanking region (tRNA Glu) were obtained for 19 Graomys griseoflaus from different karyomorphs to infer phylogenetic relationships by using maximum parsimony. Outgroups considered for this analysis were the phyllotine rodents Phyllotis xanthopygus and Eligmodontia typus cyt b sequences. Three trees were produced showing the 2n=38−34 karyomorphs grouped in a single clade while the 2n=42−41 animals formed a different one. This is in agreement with a hypothesis of a single origin for 2n=38−34 Robertsonian karyomorphs from the ancestral 2n=42.