Chromosome Painting in Two Genera of South American Monkeys: Species Identification, Conservation, and Management

Abstract

Cytogenetic studies showed that a number of New World primate taxa, particularly the genera Alouatta, Aotus, and Callicebus, have highly derived karyotypes. Cytogenetics in these primates, at every level of analysis, has contributed to the recognition of species and revealed that their number was certainly underestimated by researchers relying solely on traditional morphological data. Further attention was drawn to Alouatta and Aotus because they are characterized by translocations of the Y chromosome to autosomes, generating multiple sex chromosome systems. Here we present a report on the hybridization of human chromosome-specific paints on metaphases from 4 individuals originally assigned to Alouatta caraya and 1 individual of Aotuslemurinus. This is only the third karyotype studied with chromosome painting out of more than 10 known karyomorphs in Aotus. The banded chromosomes matched those of karyotype II as defined by Ma et al. [1976a], and we were able to more precisely assign the origin of the sample to A. l. griseimembra. Our results on the Argentinean Alouatta caraya samples were generally comparable to the banding and hybridization pattern of previous studies of A. caraya including the presence of an X₁X₁X₂X₂/X₁X₂Y₁Y₂ sex chromosome system. The karyotype of the Brazilian Alouatta sample labeled as A. caraya differs from the 3 Argentinean samples by at least 10 chromosome rearrangements. The diploid number, G banding, and hybridization pattern of this female cell line was almost identical to previous painting results on Alouatta guariba guariba. Therefore we must conclude that this cell line is actually from an A. guariba guariba individual. The contribution of cytogenetic tools in identifying species or in this case assigning individuals or cell lines to their precise taxonomic allocation is stressed. Gathering further molecular cytogenetic data on New World primates should be conservation and management priorities.

Neotropical primate evolution and phylogenetic reconstruction using chromosomal data

“…Presumably the loss of the 10a/16a association occurred by fusion with synteny 22 and a successive inversion to give 10a/22/ 16a. Aotus l. griseimembra has the least derived karyotype, while the karyomorph and A. nancymaae share four derived associations (2/12, 5/15, 9/15, 10/22) indicating a sister-clade relationship between them (Stanyon et al 2011). A peculiarity arises in the syntenic association 10/11 shown in the karyotypes of Aotus and Callicebus (Pitheciidae) (Dumas et al 2005); this association could be either a real homology phylogenetically linking the two genera or a homoplastic result of convergent evolution, or even a hemiplasy; thus, further analyses are needed through Bacterial Artificial Chromosome mapping in order to test these possible explanations.…”

“…Chromosome painting was first applied to metaphases of Aotus nancymaae, showing that the karyotype of owl monkeys is highly derived. Successively, two other Aotus karyotypes have been reconstructed: one of a karyomorph (Ruiz-Herrera et al 2005) as well as that of A. lemurinus griseimembra (Stanyon et al 2011). These three Aotus samples share the following derived associations: 1/3, 1/16, 2/20, 4/15, 7/11, 10/11, 14/15 twice and 16/22, and the loss of the ancestral New World monkey associations 2b/ 16b, 10a/16a (Figure 2(a)).…”

“…Chromosomal painting data on Lagothrix lagotricha , Ateles geoffroyi (Morescalchi et al 1997), A. belzebuth hybridus (Garcia et al 2002), A. paniscus paniscus, Brachyteles arachnoides (De Oliveira et al 2005) and six Alouatta species (Consigliere et al 1996(Consigliere et al , 1998De Oliveira et al 2002;Stanyon et al 2011) compared with the ancestral platyrrhine associations (3a/21, 5/7a, 10a/16a, 8a/18, 2b/16b, 14/15a) show that these are conserved in Atelidae. In addition, Atelidae exclusively share derived fissions of human chromosome homologs 1, 4, 5 and 15a that resulted in chromosome forms 1a1, 1a2, 4a, the association of 4b/15a2, 4c, the inversion 7a/5a/7a and 5b, 15a1/14, indicating the monophyletic origin of this group (Figure 2(b)).…”

“…Later, human chromosomal probes hybridized on metaphases of Alouatta belzebul (Consigliere et al 1996) permitted researchers to show a less rearranged karyotype than the species mentioned above. Chromosome painting has been performed on more species: A. fusca (guariba) (De Oliveira et al 2002;Stanyon et al 2011), A. caraya, A. seniculus macconnelli (De Oliveira et al 2002 and A. g. clamitans (Stanyon et al 2011). Through these works, it has been shown that the Alouatta monophyletic group is linked by a Y-autosomal translocation (Y/15b) as well as by the loss of the ancestral association 2b/16b and the presence of the association 3c/15b (except in A. belzebul).…”

The evolution of human synteny 4 by mapping sub-chromosomal specific probes in Primates

“…Our BAC mapping is in agreement with the chromosome painting results, as all probes fall on the orthologues to human chromosomes. The orthologue to human chromosome 4 in the species here considered is a submetacentric chromosome with the exception of Chlorocebus aethiops and Cercopithecus albogularis labiatus (Catarrhini), where it is fissioned (Finelli et al 1999;Moulin et al 2008) and of Lagothrix lagotricha and Aotus lemurinus griseimembra (Platyrrhini), where it has been fissioned and translocated giving new human synteny associations Stanyon et al 2011).…”