Comparative Chromosome Painting in Carnivora and Pholidota

Abstract

The order of Carnivora has been very well characterized with over 50 species analyzed by chromosome painting and with painting probe sets made for 9 Carnivora species. Representatives of almost all families have been studied with few exceptions (Otariidae, Odobenidae, Nandiniidae, Prionodontidae). The patterns of chromosome evolution in Carnivora are discussed here. Overall, many Carnivora species retained karyotypes that only slightly differ from the ancestral carnivore karyotype. However, there are at least 3 families in which the ancestral carnivore karyotype has been severely rearranged – Canidae, Ursidae and Mephitidae. Here we report chromosome painting of yet another Carnivora species with a highly rearranged karyotype, Genetta pardina. Recurrent rearrangements make it difficult to define the ancestral chromosomal arrangement in several instances. Only 2 species of pangolins (Pholidota), a sister order of Carnivora, have been studied by chromosome painting. Future use of whole-genome sequencing data is discussed in the context of solving the questions that are beyond resolution of conventional banding techniques and chromosome painting.

Classical and Molecular Cytogenetics of the Panther Genet <b><i>Genetta maculata</i></b> (Mammalia, Carnivora, Viverridae)

“…1 ). The karyotype is thus similar to that of G. maculata from Ethiopia reported by Gaubert et al [2004b], to that originally described as of G. genetta by Wurster and Benirschke [1968] but reassigned to G. maculata by Gaubert et al [2004b], and to that of G. pardina [Perelman et al, 2012]. The chromosomes in figure 1 were arranged according to the karyogram published by Perelman et al [2012].…”

“…We compared the observed banding pattern ( fig. 1 ) with the G-banded karyotypes of G. tigrina [Wurster-Hill and Gray, 1975], G. pardina [Perelman et al, 2012], and 2 species outside the large-spotted genet complex, G. genetta and Johnston's genet G. johnstoni Pocock, 1908[Gaubert et al, 2004b, and the findings are discussed below.…”

“…Previous cytogenetic studies of the order Carnivora have shown that most carnivore species have karyotypes that differ only slightly from the ACK [reviewed in Nie et al, 2012;Perelman et al, 2012]. In the suborder Caniformia, the dog-like carnivores, there are families in which the ACK has been drastically rearranged (Canidae, Mephitidae, and Ursidae), whereas in the cat-like suborder Feliformia karyotypes are highly conserved [Perelman et al, 2005].…”

“…In the suborder Caniformia, the dog-like carnivores, there are families in which the ACK has been drastically rearranged (Canidae, Mephitidae, and Ursidae), whereas in the cat-like suborder Feliformia karyotypes are highly conserved [Perelman et al, 2005]. Recently, chromosome painting of a G. pardina specimen showed it to be unique, with its highly rearranged karyotype, among 12 feliforms belonging to 5 different families [Perelman et al, 2012]. This corroborates the distinctiveness of genets observed in a G-banding comparative analysis of carnivores in which an individual of G. tigrina was studied [Wurster-Hill and Gray, 1975].…”

“…More recently, fluorescence in situ hybridization (FISH) has been used together with banding techniques in evolutionary studies of genets [Oom et al, 2010]. In the study by Perelman et al [2012], chromosome painting of the pardine genet or West African large-spotted genet G. pardina , I. Geoffroy Saint-Hilaire, 1832, showed it to have a highly rearranged karyotype compared to the ancestral carnivore karyotype (ACK), suggesting that genets may be an exception to the karyotypic conservatism in the suborder Feliformia [Perelman et al, 2005]. Gaubert et al [2004b] studied the karyotype of a G. maculata specimen from Ethiopia (2n = 52, FNa = 96), but the lack of high-quality chromosome spreads did not allow obtaining a banded karyotype.…”