Demographic histories and patterns of linkage disequilibrium in Chinese and Indian rhesus macaques

To understand the demographic history of rhesus macaques ( Macaca mulatta) and document the extent of linkage disequilibrium (LD) in the genome, we partially resequenced five Encyclopedia of DNA Elements regions in 9 Chinese and 38 captive-born Indian rhesus macaques. Population genetic analyses of the 1467 single-nucleotide polymorphisms discovered suggest that the two populations separated about 162,000 years ago, with the Chinese population tripling in size since then and the Indian population eventually shrinking by a factor of four. Using coalescent simulations, we confirmed that these inferred demographic events explain a much faster decay of LD in Chinese (r(2) approximate to 0.15 at 10 kilobases) versus Indian (r(2) approximate to 0.52 at 10 kilobases) macaque populations.