Abstract # 3173 Poster # 176:

Scheduled for Sunday, September 18, 2011 07:00 PM-09:00 PM: Session 23 (Salon G (Sixth Floor)) Poster Presentation


HYBRIDIZATION BETWEEN RHESUS AND CYNOMOLGUS MACAQUES AS INFERRED FROM ANALYSES OF PUBLISHED GENOMIC RESOURCES

C. Shih and M. H. Kohn
Department of Ecology and Evolutionary Biology, Rice University, 6100 Main St., Houston, TX 77005, USA
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Gene flow counteracts divergence between species remaining in spatial contact. If the genomes of closely related species are porous to gene flow at some loci more so than others, then a fundamental question concerns the properties common to loci subject to barriers to gene flow between species. We analyzed the rhesus macaque (Macaca mulatta) genome and thousands of cDNA reads from the cynomolgus macaque (M. fascicularis) using a Maximum-Likelihood analysis of a null model describing allopatric species divergence (i.e. no gene flow), which involves testing whether the ratios (tau/theta) of divergence time tau to coalescence time theta are equal for all genes, as is predicted by allopatric isolation. We rejected this null model, which is consistent with the hybridization between these species. Moreover, we rejected variations of the null model assuming independence of tau/theta and the evolutionary rate Ka/Ks, and independence of tau/theta and the expression of genes in testis or brain. We identified genes with Ka/Ks >0.30, and genes with enriched expression in testes, as those that are subject to barriers to gene flow between species. The genomic composition of hybrid macaques thus might not be random with respect to these parameters. Analyses of thousands of sequence reads for related species enable tests for gene flow between primate species, and enable inferences of functional genomic properties correlated with such gene flow.