Population structure of modern-day Italians reveals patterns of ancient and archaic ancestries in Southern Europe.

European populations display low genetic differentiation as the result of long-term blending of their ancient founding ancestries. However, it is unclear how the combination of ancient ancestries related to early foragers, Neolithic farmers, and Bronze Age nomadic pastoralists can explain the distribution of genetic variation across Europe. Populations in natural crossroads like the Italian peninsula are expected to recapitulate the continental diversity, but have been systematically understudied. Here, we characterize the ancestry profiles of Italian populations using a genome-wide dataset representative of modern and ancient samples from across Italy, Europe, and the rest of the world. Italian genomes capture several ancient signatures, including a non-steppe contribution derived ultimately from the Caucasus. Differences in ancestry composition, as the result of migration and admixture, have generated in Italy the largest degree of population structure detected so far in the continent, as well as shaping the amount of Neanderthal DNA in modern-day populations.

mtDNA variation in the Buryat population of the Barguzin Valley: New insights into the micro-evolutionary history of the Baikal area.

BACKGROUND: Southern Siberian populations, including the Buryat, have been of great interest in investigating the exchanges between Eastern and Western Eurasia and understanding the peopling of Siberia and the New World. AIM: Previous studies mainly employed a phylogenetic approach, and thus used pooled samples to detect a maximum of variability. As different sampling strategies may result in different pictures of a population's evolutionary history, we proposed in this study to focus on a local Buryat population selected on the basis of geographical, archaeological and ethno-historical data. SUBJECTS AND METHODS: This study investigated a local population from the Barguzin Valley, on the north-western shores of Lake Baikal identified as the most likely place of Buryat origin. We analysed mitochondrial DNA (mtDNA) RFLPs markers, HVS-I and HVS-II sequences to discuss the genetic variability of this population, and to compare our local sample with pooled Buryat samples and neighbouring Siberian populations. RESULTS: The Barguzin Buryat sample shows depressed neutrality scores compared to the pooled Buryat sample, and different genetic affinities with the Mongol and Turco-Evenk populations. CONCLUSION: These results underline the need to use local samples, in addition to pooled samples, to investigate the history of human populations at the micro-evolutionary level.

Mitochondrial DNA variation in Karkar Islanders.

We analyzed 375 base pairs (bp) of the first hypervariable region (HVS-I) of the mitochondrial DNA (mtDNA) control region and intergenic COII/tRNALys 9-bp deletion from 47 Karkar Islanders (north coast of Papua New Guinea) belonging to the Waskia Papuan language group. To address questions concerning the origin and evolution of this population we compared the Karkar mtDNA haplotypes and haplogroups to those of neighbouring East Asians and Oceanic populations. The results of the phylogeographic analysis show grouping in three different clusters of the Karkar Islander mtDNA lineages: one group of lineages derives from the first Pleistocene settlers of New Guinea-Island Melanesia, a second set derives from more recent arrivals of Austronesian speaking populations, and the third contains lineages specific to the Karkar Islanders, but still rooted to Austronesian and New Guinea-Island Melanesia populations. Our results suggest (i) the absence of a strong association between language and mtDNA variation and, (ii) reveal that the mtDNA haplogroups F1a1, M7b1 and E1a, which probably originated in Island Southeast Asia and may be considered signatures of Austronesian population movements, are preserved in the Karkar Islanders but absent in other New Guinea-Island Melanesian populations. These findings indicate that the Karkar Papuan speakers retained a certain degree of their own genetic uniqueness and a high genetic diversity. We present a hypothesis based on archaeological, linguistic and environmental datasets to argue for a succession of (partial) depopulation and repopulation and expansion events, under conditions of structured interaction, which may explain the variability expressed in the Karkar mtDNA.

Cranial discrete traits in a Byzantine population and eastern Mediterranean population movements.

Since the beginning of the Holocene, the Anatolian region has been a crossroads for populations and civilizations from Europe, Asia, and the Near to Middle East, with increasing interactions since the Bronze Age. In this context, we examine cranial discrete traits from a Byzantine population from southwest Turkey, excavated at the archeological site of Sagalassos; the site displays human occupation since the 12th millennium B.P. To investigate the biological history of this population, we analyzed the frequency distribution of 17 cranial discrete traits from Sagalassos and 27 Eurasian and African populations. Ward's clustering procedure and multidimensional scaling analyses of the standardized mean measure of divergence (MMD(st)), based on trait frequencies, were used to represent the biological affinity between populations. Our results, considered within a large interpretive framework that takes into account the idea that populations are dynamic entities affected by various influences through time and space, revealed different strata of the Sagalassos biological history. Indeed, beyond an expected biological affinity of the Sagalassos population with eastern Mediterranean populations, we also detected affinities with sub-Saharan and northern and central European populations. We hypothesize that these affinity patterns in the Sagalassos biological package are the traces of the major migratory events that affected southwest Anatolia over the last millennia, as suggested from biological, archeological, and historical data.

Mitochondrial DNA analysis of horses recovered from a frozen tomb (Berel site, Kazakhstan, 3rd Century BC).

Sequence polymorphism of the mitochondrial DNA D-loop was used to determine the genetic diversity of horses recovered from a Scythian princely tomb dating from the beginning of the 3rd century BC. Eight haplotypes were found among the 13 ancient horse samples tested. Phylogenetical analysis showed that these ancient horse's sequences, along with two Yakut ones, were distributed throughout the tree defined by modern horses' sequences and are closely related to them. No clear geographical affiliation of the specimens studied was thus determined. Our work, among others, supports the very ancient origin of the matrilines in horses.

Testing for kavain in human hair using gas chromatography-tandem mass spectrometry.

A sensitive, specific and reproducible method for the quantitative determination of kavain in human hair has been developed. The sample preparation involved a decontamination step of the hair with methylene chloride. The hair sample (about 50 mg) was incubated in 1 ml of methanol for 1 h, in an ultrasonic bath, in presence of 20 ng of methaqualone-d7 used as internal standard. The methanolic solution was evaporated to dryness, and the residue reconstituted by adding 30 microl of methanol. A 2 microl aliquot of the extract was injected onto the column (Optima5-MS capillary column, 5% phenyl-95% methylsiloxane, 30 m x 0.25 mm i.d. x 0.25 mm film thickness) of a Hewlett-Packard (Palo Alto, CA) gas chromatograph (5890). Kavain was detected by its parent ion at m/z 230 and daughter ions at m/z 111 and 202 through a Finnigan TSQ 700 MS/MS system. The assay was capable of detecting 30 pg/mg of kavain (limit of detection (LOD)). Linearity was observed for kavain concentrations ranging from 100 to 2000 pg/mg with a correlation coefficient of 0.998. Intra-day precision at 400 pg/mg was 13.7%. The analysis of a segment of hair, obtained from an occasional consumer, revealed the presence of kavain at the concentration of 418 pg/mg. A higher concentration (1708 pg/mg) was detected in the corresponding pubic hair.