Genetic data on North and Central Asian populations are underrepresented in the literature, especially for autosomal markers. In the present study we used 812 single nucleotide polymorphisms (SNPs) distributed across all the human autosomes and extensively studied at Yale to examine the affinities of two recently collected samples of populations: rural and cosmopolitan Mongolians from Ulaanbaatar and nomadic, Turkic-speaking Tsaatan from Mongolia near the Siberian border. We compare these two populations with each other and with a global set of populations and discuss their relationships to New World populations. Specifically, we analyze data on 521 autosomal loci (single SNPs and multi-SNP haplotypes) studied in 57 populations representing all the major geographical regions of the world. We conclude that these North and Central Asian populations are genetically distinct from all other populations in our study and may be close to the ancestral lineage leading to the New World populations.

Otitis media (OM; inflammation of the middle ear) comprises a group of disorders that are among the most common disorders of childhood. OM is also heritable and has effects on fecundity. This means that OM is subject to evolution, yet the evolutionary forces that may determine susceptibility to OM have not been adequately explored. Here I analyze evolutionary forces that may determine susceptibility to middle ear inflammation. These forces include those affecting function of the middle ear, host immunity, or colonization by and pathogenicity of bacteria. I review existing evolutionary models of host-pathogen interaction and coevolution and apply these to better understand the complex evolutionary landscape of middle ear infection and inflammation in humans, including factors determining transition between stable evolutionary strategies for host and bacteria. This understanding is then applied to an analysis of OM in indigenous populations to devise a new theory for OM prevalence in Australian Aborigine, Native American, Inuit, and Maori populations. I suggest that high prevalence in such groups may have resulted from encounters of these previously isolated populations with European immigrants in the 15th and 16th centuries. This exposed them to new strains of bacteria to which their immune system had not evolved immunity, perturbing a previously stable host-pathogen coevolutionary state.

Determining the origins of those buried within undocumented cemeteries is of incredible importance to historical archaeologists and, in many cases, the nearby communities. In the case of Avondale Burial Place, a cemetery in Bibb County, Georgia, in use from 1820 to 1950, all written documentation of those interred within it has been lost. Osteological and archaeological evidence alone could not describe, with confidence, the ancestral origins of the 101 individuals buried there. In the present study, we used ancient DNA extraction methods in well-preserved skeletal fragments from 20 individuals buried in Avondale Burial Place to investigate the origins of the cemetery. Through examination of hypervariable region I (HVR1) in the mitochondrial genome (mtDNA), we determined haplotypes for all 20 of these individuals. Eighteen of these individuals belong to the L or U haplogroups, suggesting that Avondale Burial Place was most likely used primarily as a resting place for African Americans. After the surrounding Bibb County community expressed interest in investigating potential ancestral relationships to those within the cemetery, eight potential descendants provided saliva to obtain mtDNA HVR1 information. Three individuals from Avondale Burial Place matched three individuals with oral history ties to the cemetery. Using the online tool EMPOP, we calculated the likelihood of these exact matches occurring by chance alone (< 1%). The present findings exhibit the importance of genetic analysis of cemetery origins when archaeological and osteological data are inconclusive for estimating ancestry of anonymous historical individuals.

The existing relationship between human populations is a function of their migratory and genetic exchange, which will be inversely proportional to the distance separating them. The effect of geographic distance on population structure may be estimated by means of isonymic methods that use information on the surnames present in a territory as an approximation to the distribution of allele frequencies. The objective of this study was to analyze whether the 1801 modification of the political border in an area surrounding the town of Olivenza, which experienced a change of sovereignty from Portugal to Spain, has had a noticeable influence on the migration pattern and isolation by distance in that region. For this purpose, data from marriage records of Olivenza and the neighboring Portuguese municipalities of Alandroal, Juromenha, Elvas, Vila Boim (and Terrugem), Terena, Monsaraz, and Vila Viçosa were analyzed. Rates of diversity and inbreeding coefficients were determined to analyze the population structure before (1775–1801) and after (1802–1825) the change of domain. The results show that after the border modification the migration matrices changed differently according to sex, therefore altering the relationship between the various localities of the territory. In Olivenza inbreeding declined slightly and surnames became more heterogeneous. Moreover, after the change of domain the isolation-by-distance models illustrate a temporal reduction in the relative weight of geographical distance on interpopulation kinship. The political border acted as a factor in population differentiation in the Iberian Peninsula (Spain and Portugal).