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Osteogenesis imperfecta (imperfect osteogenesis in the Russian literature) is the most common hereditary form of bone fragility, it is a genetically and clinically heterogeneous disease with a wide range of clinical severity, often leading to disability from early childhood. It is based on genetic disorders leading to a violation of the structure of bone tissue, which leads to frequent fractures, impaired growth and posture, with the development of characteristic disabling bone deformities and associated problems, including respiratory, neurological, cardiac, renal impairment, hearing loss. Osteogenesis imperfecta occurs in both men and women, the disease is inherited in both autosomal dominant and autosomal recessive types, there are sporadic cases of the disease due to de novo mutations, as well as X-linked forms. The term "osteogenesis imperfecta" was coined by W. Vrolick in the 1840s. The first classification of the disease was made in 1979 and has been repeatedly reviewed due to the identification of the molecular cause of the disease and the discovery of new mechanisms for the development of osteogenesis imperfecta. In the early 1980s, mutations in two genes of collagen type I (COL1A1 and COL1A2) were first associated with an autosomal dominant inheritance type of osteogenesis imperfecta. Since then, 18 more genes have been identified whose products are involved in the formation and mineralization of bone tissue. The degree of genetic heterogeneity of the disease has not yet been determined, researchers continue to identify new genes involved in its pathogenesis, the number of which has reached 20. In the last decade, it has become known that autosomal recessive, autosomal dominant and X-linked mutations in a wide range of genes, encoding proteins that are involved in the synthesis of type I collagen, its processing, secretion and post-translational modification, as well as in proteins that regulate the differentiation and activity of bone-forming cells, cause imperfect osteogenesis. A large number of causative genes complicated the classical classification of the disease and, due to new advances in the molecular basis of the disease, the classification of the disease is constantly being improved. In this review, we systematized and summarized information on the results of studies in the field of clinical and genetic aspects of osteogenesis imperfecta and reflected the current state of the classification criteria for diagnosing the disease.Незавершенный остеогенез (несовершенный остеогенез в русскоязычной литературе) – наиболее распространенная наследственная форма ломкости костей, генетически и клинически гетерогенное заболевание с широким спектром клинической тяжести, основное клиническое проявление которого – множественные переломы начиная с натального периода жизни, зачастую приводящие к инвалидизации с детского возраста. К основным клиническим признакам незавершенного остеогенеза относятся голубые склеры, потеря слуха, аномалия дентина, повышенная ломкость костей, нарушение роста и осанки с развитием характерных инвалидизирующих деформаций костей и сопутствующих проблем, включающих дыхательные, неврологические, сердечные, почечные нарушения. Незавершенный остеогенез встречается и у мужчин, и у женщин, заболевание наследуется как по аутосомно-доминантному, так и аутосомно-рецессивному типам, существуют спорадические случаи заболевания, обусловленные мутациями de novo, а также обнаружены Х-сцепленные формы. Термин «незавершенный остеогенез» был введен W. Vrolick в 1840-х гг. Первая классификация заболевания сделана в 1979 г. и неоднократно пересматривалась из-за идентификации молекулярной причины заболевания и открытия новых механизмов развития незавершенного остеогенеза. В начале 1980-х гг. мутации в двух генах коллагена типа I (COL1A1 и COL1A2) впервые были ассоциированы с аутосомно-доминантным типом наследования незавершенного остеогенеза. С тех пор идентифицированы еще 18 генов, продукты которых участвуют в процессах формирования и минерализации костной ткани. До сих пор не определена степень генетической гетерогенности заболевания, исследователи продолжают идентифицировать новые гены, вовлеченные в его патогенез, число которых достигло 20. В последнее десятилетие стало известно, что аутосомно-рецессивные, аутосомно-доминантные и Х-связанные мутации в широком спектре генов, кодирующих белки, участвующие в синтезе коллагена типа I, его процессинге, секреции и посттрансляционной модификации, а также в белках, регулирующих дифференцировку и активность костеобразующих клеток, вызывают несовершенный остеогенез. Большое количество причинных генов усложнило классическую классификацию заболевания, и в связи с новыми достижениями в области молекулярных основ незавершенного остеогенеза постоянно совершенствуется и классификация. В этом обзоре мы систематизировали и обобщили информацию о результатах исследований в области изучения клинико-генетических аспектов незавершенного остеогенеза и отразили современное состояние классификационных критериев диагностики заболевания.

Kalmyks, the only Mongolic-speaking population in Europe, live in the southeast of the European Plain, in Russia. They adhere to Buddhism and speak a dialect of the Mongolian language. Historical and linguistic evidence, as well a shared clan names, suggests a common origin with Oirats of western Mongolia; yet, only a limited number of genetic studies have focused on this topic. Here we compare the paternal genetic relationship of Kalmyk clans with ethnographically related groups from Mongolia, Kyrgyzstan and China, within the context of their neighbouring populations. A phylogeny of 37 high-coverage Y-chromosome sequences, together with further genotyping of larger sample sets, reveals that all the Oirat-speaking populations studied here, including Kalmyks, share, as a dominant paternal lineage, Y-chromosomal haplogroup C3c1-M77, which is also present in several geographically distant native Siberian populations. We identify a subset of this clade, C3c1b-F6379, specifically enriched in Kalmyks as well as in Oirat-speaking clans in Inner Asia. This sub-clade coalesces at around 1500 years before present, before the Genghis Khan era, and significantly earlier than the split between Kalmyks and other Oirat speakers about 400 years ago. We also show that split between the dominant hg C variant among Buryats—C3-M407—and that of C3-F6379, took place in the Early Upper Palaeolithic, suggesting an extremely long duration for the dissipation of hg C3-M217 carriers across northern Eurasia, which cuts through today’s major linguistic phyla.

Osteoporosis is one of multifactorial diseases, it develops from interactions between the genetic component and the environment. However, the universal epigenetic markers of osteoporosis are not yet defined. Finding the risk factors will predict the risk of osteoporosis at the preclinical stage, help define the course and severity of the disease, and develop preventive measures based on them to reduce the risk of fractures. Expanding knowledge in the field of bone biology, especially in the genetics of osteoporosis and osteoimmunology, showed that osteoporosis is a disease that occurs not only due to hormonal or mechanical disorders, but also as a clinically and genetically heterogeneous disease, and there are still unknown pathogenetic links in its structure. Decreases in bone mass and matrix mineralization as well as changes in bone microarchitecture can have different pathogenetic patterns of development and, moreover, there are unknown links of the pathogenesis of osteoporosis. It is possible that DNA methylation is one of these links and a mechanism for epigenetic regulation of gene expression. Evidence exists that this mechanism alongside regulatory miRNAs and post-translational modifications makes a significant contribution to the central processes of bone remodeling; however, the results of various studies vary greatly, and, therefore, there is a need to understand the significance of the accumulated data and to make them consistent. The purpose of this review is to compile and systematize data on the role of DNA methylation in bone metabolism in normal and pathological conditions, in the formation of osteoporosis, and to assess achievements and trends in this field of research and technologies for studying DNA methylation.

Over the past decades, numerous studies on the genetic markers of osteoarthritis (OA) have been conducted. MiRNA targets sites are a promising new area of research. In this study, we analyzed the polymorphic variants in 3′ UTR regions of COL1A1, COL11A1, ADAMTS5, MMP1, MMP13, SOX9, GDF5, FGF2, FGFR1, and FGFRL1 genes to examine the association between miRNA target site alteration and the incidence of OA in women from the Volga-Ural region of Russia using competitive allele-specific PCR. The T allele of the rs9659030 was associated with generalized OA (OR = 2.0), whereas the C allele of the rs229069 was associated with total OA (OR = 1.43). The T allele of the rs13317 was associated with the total OA (OR = 1.67). After Benjamini-Hochberg correction, only rs13317 remained statistically significant. According to ethnic heterogeneity, associations between the T allele (rs1061237) with OA in women of Russian descent (OR = 1.77), the G allele (rs6854081) in women of Tatar descent (OR = 4.78), the C allele (rs229069) and the T allele (rs73611720) in women of mixed descent and other ethnic groups (OR = 2.25 and OR = 3.02, respectively) were identified. All associations remained statistically significant after Benjamini-Hochberg correction. Together, this study identified miRNA target sites as a genetic marker for the development of OA in various ethnic groups.

In recent genome-wide association studies (GWAS), several polymorphic loci of the osteoprotegerin (OPG) gene were significantly associated with bone mineral density (BMD) and fractures in men over 50 years of age and postmenopausal women. The objective of our study was to search for associations of rs3102735, rs3134069, rs2073617, rs2073618, rs3102734 and rs7844539 of the OPG gene with the risk of osteoporotic fractures and the level of BMD in individual and comorbid conditions in men and women from the Volga-Ural region of Russia. Material and Methods — 828 women and 496 men of various ethnic groups (Russians, Turks) were examined using two-energy x-ray absorptiometry (DEXA) in the femoral neck and lumbar spine. 1324 deoxyribonucleic acid (DNA) samples were genotyped using a fluorescent endpoint genotyping system, after that we searched for associations of these polymorphic loci with fractures and low BMD levels of various localizations. As a result, there was a significant association of rs3134069 and rs3102734 with fractures in general and in the peripheral parts of the skeleton, as well as rs7844539 and rs3102734 in women and rs2073618 in men with low BMD. Another significant association of rs3102734 and rs2073618 with low bone mineral density in the femoral neck was found in both genders. Conclusion — Polymorphic variants rs3134069, rs3102734, rs7844539 and rs3102734 are potential markers of the risk of osteoporetic fractures and the formation of low BMD in men and women from the Volga-Ural region of Russia.

Intracranial aneurysm (IA) is a complex disease resulting in subarachnoid hemorrhage (SAH) due to a rupture. The average worldwide prevalence of this disease is about 2–5 %, with 50 % of them ending in death or neurological disorders of varying severity, with a high probability of recurrence of hemorrhage during the frst half of the year after rupture. Subarachnoid hemorrhage is annually registered in at least 18 thousand people in Russia. Associations of polymorphic variantsrs594942andrs11603042of theVEGFBgene in intracranial aneurysm development in the Volga-Ural region of the Russian Federation with the presence of the symptom complex of undifferentiated connective tissue dysplasia (uDST) and arterial hypertension (AH) were investigated. TheC* allelers594942andrs11603042of theVEGFBgene is a marker of an increased risk of IA as a whole (p= 0.025; χ2 = 5.052; OR = 1.32) in women as a whole (p= 0.001; χ2 = 10.124; OR = 1.70) and in comorbid state with uDCT (p= 0.002; χ2 = 9.501; OR = 2.34) and AG (p= 0.006; χ2 = 7.385; OR = 2.109). We found that the genotype *C*Cof locusrs594942of theVEGFBgene is a marker of an increased risk of intracranial aneurysm in general (p= 0.017; χ2 = 5.702; OR = 1.49) and among women in general (p= 0.0005; χ2 = 12.078; OR = 2.25) and with the symptomatic complex uCTD (p= 0.007; χ2 = 7.173; OR = 2.67) and AH (p= 0.010; χ2 = 6.471; OR = 2.51). We have obtained new results on the role of polymorphic variants of theVEGFBgene in the formation of intracranial aneurysm, taking into account the presence of the symptom complex uDCT and AH among the residents of the Volga-Ural region of Russia. A burdened comorbid background and the presence of undifferentiated connective tissue dysplasia and arterial hypertension can contribute to an increased risk of intracranial aneurysm, as evidenced by the results of our study.

Objective — The aim of the work was to study serum concentrations of magnesium, copper, zinc, phosphorus and calcium in individuals with undifferentiated connective tissue dysplasia (uCTD) and joint hypermobility (JH) in an isolated and combined state. Material and methods — the concentrations of magnesium, copper, zinc, phosphorus and calcium were measured by the direct colorimetric method in 55 people with joint hypermobility and in 34 – without hypermobility. Results — There were no significant differences between serum concentrations of microelementsin groups with and without JH. In patients with mild and severe uCTD significant decrease in serum magnesium concentrations was noted (U=2.12, p=0.034 and U=3.7, p=0.012). In patients with isolated JH significant serum zinc concentrationdecrease was revealed compared with the control group (U=3.12, p=0.022). Serum magnesium concentrations were reduced in all patients with uCTD and JH; in the groups with isolated dysplasia and combined pathology, the differences reached the level of statistical significance (U=2.78, p=0.024 and U=3.2, p=0.018). Conclusion — The study revealed significant associations of a decrease in serum magnesium concentrations with the development of uCTD in an isolated and combined with JH state and decrease in serum zinc concentrations with the development of isolated JH.

Background The history of human populations occupying the plains and mountain ridges separating Europe from Asia has been eventful, as these natural obstacles were crossed westward by multiple waves of Turkic and Uralic-speaking migrants as well as eastward by Europeans. Unfortunately, the material records of history of this region are not dense enough to reconstruct details of population history. These considerations stimulate growing interest to obtain a genetic picture of the demographic history of migrations and admixture in Northern Eurasia. Results We genotyped and analyzed 1076 individuals from 30 populations with geographical coverage spanning from Baltic Sea to Baikal Lake. Our dense sampling allowed us to describe in detail the population structure, provide insight into genomic history of numerous European and Asian populations, and significantly increase quantity of genetic data available for modern populations in region of North Eurasia. Our study doubles the amount of genome-wide profiles available for this region. We detected unusually high amount of shared identical-by-descent (IBD) genomic segments between several Siberian populations, such as Khanty and Ket, providing evidence of genetic relatedness across vast geographic distances and between speakers of different language families. Additionally, we observed excessive IBD sharing between Khanty and Bashkir, a group of Turkic speakers from Southern Urals region. While adding some weight to the “Finno-Ugric” origin of Bashkir, our studies highlighted that the Bashkir genepool lacks the main “core”, being a multi-layered amalgamation of Turkic, Ugric, Finnish and Indo-European contributions, which points at intricacy of genetic interface between Turkic and Uralic populations. Comparison of the genetic structure of Siberian ethnicities and the geography of the region they inhabit point at existence of the “Great Siberian Vortex” directing genetic exchanges in populations across the Siberian part of Asia. Slavic speakers of Eastern Europe are, in general, very similar in their genetic composition. Ukrainians, Belarusians and Russians have almost identical proportions of Caucasus and Northern European components and have virtually no Asian influence. We capitalized on wide geographic span of our sampling to address intriguing question about the place of origin of Russian Starovers, an enigmatic Eastern Orthodox Old Believers religious group relocated to Siberia in seventeenth century. A comparative reAdmix analysis, complemented by IBD sharing, placed their roots in the region of the Northern European Plain, occupied by North Russians and Finno-Ugric Komi and Karelian people. Russians from Novosibirsk and Russian Starover exhibit ancestral proportions close to that of European Eastern Slavs, however, they also include between five to 10 % of Central Siberian ancestry, not present at this level in their European counterparts. Conclusions Our project has patched the hole in the genetic map of Eurasia: we demonstrated complexity of genetic structure of Northern Eurasians, existence of East-West and North-South genetic gradients, and assessed different inputs of ancient populations into modern populations. Electronic supplementary material The online version of this article (10.1186/s12863-017-0578-3) contains supplementary material, which is available to authorized users.

Analysis of the carrier frequency of p.Arg408Trp, p.Arg261Gln, and p.Arg261X mutations in the PAH gene was carried out in different unrelated indigenous individuals representing 58 populations of Eurasia taking into account their linguistic identity and territorial location. Mutation p.Arg408Trp in the PAH gene was found in 14 studied populations with the highest average carrier frequency of 0.0127 in the Volga-Ural region and 0.0134 in the representatives of the Slavic language group. Mutation p.Arg261Gln in the PAH gene was detected only in two populations with average carrier frequency rate of 0.0012 in the Volga-Ural region. Mutation p.Arg261X in the PAH gene was identified in four North Caucasus populations with highest carrier frequency in Karachays—at 0.0526. All PAH gene mutations in populations of Eurasia were identified in the heterozygous state.

We conducted an association study of ten polymorphisms in six candidate genes of OA (rs1799750 (MMP1), rs35068180 (MMP3), rs2252070 (MMP13), rs63118460 and rs2276455 (COL2A1), rs143383 (GDF5), rs1544410, rs7975232, rs731236, and rs2228570 (VDR)) with the development of osteoarthritis (OA) in 333 women taking into account the localization of the pathological process, the age of disease manifestation, and ethnicity and investigated the presence of signs of undifferentiated connective tissue dysplasia (UCTD). On the basis of clinical and genetic data, we revealed statistically significant models to predict the development of osteoarthritis of various localizations (knee, hip, and generalized forms).

The genetic diversity in two ethnic groups of the central part of the North Caucasus (Balkars and Karachays) using 50 diallelic loci in the non-recombining region of the Y chromosome was analyzed. For the first time, an analysis of distribution of frequencies of Y-chromosome haplogroups in Balkars considering different subethnic groups (Baksans, Chegems, Kholams, Bezengiyevs, and Malkars) was conducted. The major Y-chromosome haplogroups in the studied groups of Balkars and Karachays were G2a-P16 and R1a- Z2123. In addition, for a better understanding of genetic relationship between the male lineages in the studied populations and other populations of the Caucasus, we performed an analysis of R1a-M198 subhaplogroups in 22 populations of this region. The principal component analysis demonstrated that a greater difference was observed between Kholams and the other Balkar subgroups. According to the F st analysis, Chegems, for which the prevalence of haplogroup R1b-M478 (32.2%) was reported, demonstrated the maximum difference from the other subpopulations of Balkars and Karachays.

Here we report the Simons Genome Diversity Project data set: high quality genomes from 300 individuals from 142 diverse populations. These genomes include at least 5.8 million base pairs that are not present in the human reference genome. Our analysis reveals key features of the landscape of human genome variation, including that the rate of accumulation of mutations has accelerated by about 5% in non-Africans compared to Africans since divergence. We show that the ancestors of some pairs of present-day human populations were substantially separated by 100,000 years ago, well before the archaeologically attested onset of behavioural modernity. We also demonstrate that indigenous Australians, New Guineans and Andamanese do not derive substantial ancestry from an early dispersal of modern humans; instead, their modern human ancestry is consistent with coming from the same source as that of other non-Africans., Facultad de Ciencias Naturales y Museo

High-coverage whole-genome sequence studies have so far focused on a limited number1 of geographically restricted populations2, 3, 4, 5, or been targeted at specific diseases, such as cancer6. Nevertheless, the availability of high- resolution genomic data has led to the development of new methodologies for inferring population history7, 8, 9 and refuelled the debate on the mutation rate in humans10. Here we present the Estonian Biocentre Human Genome Diversity Panel (EGDP), a dataset of 483 high-coverage human genomes from 148 populations worldwide, including 379 new genomes from 125 populations, which we group into diversity and selection sets. We analyse this dataset to refine estimates of continent-wide patterns of heterozygosity, long- and short-distance gene flow, archaic admixture, and changes in effective population size through time as well as for signals of positive or balancing selection. We find a genetic signature in present-day Papuans that suggests that at least 2% of their genome originates from an early and largely extinct expansion of anatomically modern humans (AMHs) out of Africa. Together with evidence from the western Asian fossil record11, and admixture between AMHs and Neanderthals predating the main Eurasian expansion12, our results contribute to the mounting evidence for the presence of AMHs out of Africa earlier than 75, 000 years ago.

The paternal haplogroup (hg) N is distributed from southeast Asia to eastern Europe. The demographic processes that have shaped the vast extent of this major Y chromosome lineage across numerous linguistically and autosomally divergent populations have previously been unresolved. On the basis of 94 high-coverage re-sequenced Y chromosomes, we establish and date a detailed hg N phylogeny. We evaluate geographic structure by using 16 distinguishing binary markers in 1,631 hg N Y chromosomes from a collection of 6,521 samples from 56 populations. The more southerly distributed sub-clade N4 emerged before N2a1 and N3, found mostly in the north, but the latter two display more elaborate branching patterns, indicative of regional contrasts in recent expansions. In particular, a number of prominent and well-defined clades with common N3a3'6 ancestry occur in regionally dissimilar northern Eurasian populations, indicating almost simultaneous regional diversification and expansion within the last 5,000 years. This patrilineal genetic affinity is decoupled from the associated higher degree of language diversity.

Background and Purpose—Genomewide DNA linkage analysis identified a susceptibility locus for intracranial aneurysm (IA) on chromosome 19q13 in the Finnish population, a region including the kallikrein gene cluster. We investigated the association of single nucleotide polymorphisms (SNPs) in the kallikrein gene cluster with IA in the Finnish population.Methods—We genotyped 18 haplotype-tagging SNPs spanning a 244 kbp region in the kallikrein gene cluster for 266 Finnish IA cases and 290 Finnish control subjects. In a second phase, we genotyped 2 SNPs (rs1722561 and rs1701946) in an additional set of 102 Finnish IA cases and 102 Finnish control subjects; and in a third phase, we genotyped these 2 SNPs in 156 Russian IA cases and 186 Russian control subjects. Both single-marker and haplotype-based tests of association were performed.Results—In phase I, SNPs rs1722561 and rs1701946 were significantly associated with IA in the Finnish population for single locus models (rs1722561:P=0.0395; rs1701946:P=0.0253). A 2-SNP haplotype block (rs1722561–rs1701946) identified in phase I was also associated with IA in the expanded Finnish (phase II) data set (asymptoticP=0.012; empiricalP=0.019). In the Finnish and Russian combined data set (phase III) with 524 cases and 578 control subjects, the same 2 SNPs (OR: 1.35, 95% CI: 1.14, 1.60;P=0.0005 for rs1722561 and OR: 1.32, 95% CI: 1.12, 1.57;P=0.0011 for rs1701946) were significantly associated with IA. These SNPs are located in the intronic region ofKLK8, although linkage disequilibrium could extend from rs268912–rs2250066, a ≈76-kbp region that includes KLK5–KLK10.Conclusions—Polymorphisms within the kallikrein gene cluster are associated with IA suggesting that the kallikreins are important candidate genes for IA.

It is commonly thought that human genetic diversity in non-African populations was primarily shaped by a recent out-of-Africa dispersal. Here we present a large geographical Y chromosome study using 459 high coverage sequences, including 302 newly reported here. We date the Y chromosomal Most Recent Common Ancestor (MRCA) in Africa at 254 (95% CI 192- 307) kya and differentiation of African and non-African lineages 52-121 kya. The age estimates for major non-African founder haplogroups cluster closely in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. We find that the highest basal Y chromosome diversity outside Africa has been preserved in South and Southeast Asians while extant Y chromosome diversity in Europe and the Near East stems from a small number of mid-Holocene founders. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck, followed by a fast recovery in Old World populations dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.

We sequenced the genomes of a ∼7,000-year-old farmer from Germany and eight ∼8,000-year-old hunter-gatherers from Luxembourg and Sweden. We analysed these and other ancient genomes1,2,3,4 with 2,345 contemporary humans to show that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians3, who contributed to both Europeans and Near Easterners; and early European farmers, who were mainly of Near Eastern origin but also harboured west European hunter-gatherer related ancestry. We model these populations’ deep relationships and show that early European farmers had ∼44% ancestry from a ‘basal Eurasian’ population that split before the diversification of other non-African lineages., Instituto Multidisciplinario de Biología Celular

International audience; Haplogroup G, together with J2 clades, has been associated with the spread of agriculture, especially in the European context. However, interpretations based on simple haplogroup frequency clines do not recognize underlying patterns of genetic diversification. Although progress has been recently made in resolving the haplogroup G phylogeny, a comprehensive survey of the geographic distribution patterns of the significant sub-clades of this haplogroup has not been conducted yet. Here we present the haplogroup frequency distribution and STR variation of 16 informative G sub-clades by evaluating 1472 haplogroup G chromosomes belonging to 98 populations ranging from Europe to Pakistan. Although no basal G-M201* chromosomes were detected in our data set, the homeland of this haplogroup has been estimated to be somewhere nearby eastern Anatolia, Armenia or western Iran, the only areas characterized by the co-presence of deep basal branches as well as the occurrence of high sub-haplogroup diversity. The P303 SNP defines the most frequent and widespread G sub-haplogroup. However, its sub-clades have more localized distribution with the U1-defined branch largely restricted to Near/Middle Eastern and the Caucasus, whereas L497 lineages essentially occur in Europe where they likely originated. In contrast, the only U1 representative in Europe is the G-M527 lineage whose distribution pattern is consistent with regions of Greek colonization. No clinal patterns were detected suggesting that the distributions are rather indicative of isolation by distance and demographic complexities.

Sexual dimorphism in various bone phenotypes, including bone mineral density (BMD), is widely observed; however, the extent to which genes explain these sex differences is unclear. To identify variants with different effects by sex, we examined gene-by-sex autosomal interactions genome-wide, and performed expression quantitative trait loci (eQTL) analysis and bioinformatics network analysis. We conducted an autosomal genome-wide meta-analysis of gene-by-sex interaction on lumbar spine (LS) and femoral neck (FN) BMD in 25,353 individuals from 8 cohorts. In a second stage, we followed up the 12 top single-nucleotide polymorphisms (SNPs; p −5) in an additional set of 24,763 individuals. Gene-by-sex interaction and sex-specific effects were examined in these 12 SNPs. We detected one novel genome-wide significant interaction associated with LS-BMD at the Chr3p26.1-p25.1 locus, near the GRM7 gene (male effect = 0.02 and p = 3.0 × 10−5; female effect = −0.007 and p = 3.3 × 10−2), and 11 suggestive loci associated with either FN- or LS-BMD in discovery cohorts. However, there was no evidence for genome-wide significant (p −8) gene-by-sex interaction in the joint analysis of discovery and replication cohorts. Despite the large collaborative effort, no genome-wide significant evidence for gene-by-sex interaction was found to influence BMD variation in this screen of autosomal markers. If they exist, gene-by-sex interactions for BMD probably have weak effects, accounting for less than 0.08% of the variation in these traits per implicated SNP.

The Caucasus, inhabited by modern humans since the Early Upper Paleolithic and known for its linguistic diversity, is considered to be important for understanding human dispersals and genetic diversity in Eurasia. We report a synthesis of autosomal, Y chromosome, and mitochondrial DNA (mtDNA) variation in populations from all major subregions and linguistic phyla of the area. Autosomal genome variation in the Caucasus reveals significant genetic uniformity among its ethnically and linguistically diverse populations and is consistent with predominantly Near/Middle Eastern origin of the Caucasians, with minor external impacts. In contrast to autosomal and mtDNA variation, signals of regional Y chromosome founder effects distinguish the eastern from western North Caucasians. Genetic discontinuity between the North Caucasus and the East European Plain contrasts with continuity through Anatolia and the Balkans, suggesting major routes of ancient gene flows and admixture.