Phylogenomics of species from four genera of New Word monkeys by flow sorting and reciprocal chromosome painting

摘要

Background: The taxonomic and phylogenetic relationships of New World monkeys (Platyrrhini) are difficult to\uddistinguish on the basis of morphology and because diagnostic fossils are rare. Recently, molecular data have led to a\udradical revision of the traditional taxonomy and phylogeny of these primates. Here we examine new hypotheses of\udplatyrrhine evolutionary relationships by reciprocal chromosome painting after chromosome flow sorting of species\udbelonging to four genera of platyrrhines included in the Cebidae family: Callithrix argentata (silvered-marmoset), Cebuella\udpygmaea (pygmy marmoset), Callimico goeldii (Goeldi's marmoset) and Saimiri sciureus (squirrel monkey). This is the first\udreport of reciprocal painting in marmosets.\udResults: The paints made from chromosome flow sorting of the four platyrrhine monkeys provided from 42 to 45\udhybridization signals on human metaphases. The reciprocal painting of monkey probes on human chromosomes revealed\udthat 21 breakpoints are common to all four studied species. There are only three additional breakpoints. A breakpoint\udon human chromosome 13 was found in Callithrix argentata, Cebuella pygmaea and Callimico goeldii, but not in Saimiri\udsciureus. There are two additional breakpoints on human chromosome 5: one is specific to squirrel monkeys, and the\udother to Goeldi's marmoset.\udConclusion: The reciprocal painting results support the molecular genomic assemblage of Cebidae. We demonstrated\udthat the five chromosome associations previously hypothesized to phylogenetically link tamarins and marmosets are\udhomologous and represent derived chromosome rearrangements. Four of these derived homologous associations tightly\udnest Callimico goeldii with marmosets. One derived association 2/15 may place squirrel monkeys within the Cebidae\udassemblage. An apparently common breakpoint on chromosome 5q33 found in both Saimiri and Aotus nancymae could be\udevidence of a phylogenetic link between these species. Comparison with previous reports shows that many syntenic\udassociations found in platyrrhines have the same breakpoints and are homologous, derived rearrangements showing that\udthe New World monkeys are a closely related group of species. Our data support the hypothesis that the ancestral\udkaryotype of the Platyrrhini has a diploid number of 2n = 54 and is almost identical to that found today in capuchin\udmonkeys; congruent with a basal position of the Cebidae among platyrrhine families.