Gene-flow from an ancestrally differentiated group has been shown to be a powerful source of selectively advantageous variants. To understand whether recent gene-flow may have contributed to adaptation among humans in sub-Saharan Africa, we applied a novel method to identify deviations in ancestry inferred from genome-wide data in 48 populations. Among the signals of ancestry deviation that we find in the Fula, an historically pastoralist ethnic group from the Gambia, are the region that encodes the lactose persistence phenotype, LCT/MCM6, which has the highest proportion of Eurasian ancestry in the genome. The region with the lowest proportion of non-African ancestry is across DARC, which encodes the Duffy null phenotype and is protective for Plasmodium vivax malaria. In the Jola from the Gambia and a Khoesan speaking group from Namibia we find multiple regions with inferred ancestry deviation including the Major Histocompatibility Complex. Our analysis shows the potential for adaptive gene-flow in recent human history.

In spite of the widespread use of rhesus monkeys (Macaca mulatta) in biomedical research, MHC typing of this species is not yet routine. Since suitable antibodies are lacking, serological typing of Mamu-DQA1 is not feasible. We developed a typing protocol for MhcMamu-DQA1 from published sequences of the second exon of Mamu-DQA1. This protocol is based on the amplification of the second exon of Mamu-DQA1 with one specific primer pair followed by a "diagnostic" digestion of the PCR products with, at most, 5 different restriction endonucleases. This modified PCR-RFLP permits the rapid identification of 11 out of 13 Mamu-DQA1 alleles in homozygous and heterozygous combinations. The protocol was validated by cloning and sequencing the PCR-products of several animals of different geographic origin. In addition, an as yet unknown allele was detected by PCR-RFLP and was subsequently cloned and its nucleotide sequence determined. All examined sequences except the new allele were identical to those previously published. Therefore, we assume that many of the Mamu-DQA1 alleles of rhesus monkeys have been identified molecularly and that the typing technique presented here can reliably identify Mamu-DQA1 alleles.

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