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Balanovsky O.P.,Russian Academy of Medical Sciences | Koshel S.M.,Moscow State University | Pshenichnov A.S.,Russian Academy of Medical Sciences | Frolova S.A.,Russian Academy of Medical Sciences | And 9 more authors.
Russian Journal of Genetics | Year: 2011

Yu. P. Altukhov suggested that heterozygosity is an indicator of the state of the gene pool. The idea and a linked concept of genetic ecological monitoring were applied to a new dataset on mtDNA variation in East European ethnic groups. Haplotype diversity (an analog of the average heterozygosity) was shown to gradually decrease northwards. Since a similar trend is known for population density, interlinked changes were assumed for a set of parameters, which were ordered to form a causative chain: latitude increases, land productivity decreases, population density decreases, effective population size decreases, isolation of subpopulations increases, genetic drift increases, and mtDNA haplotype diversity decreases. An increase in genetic drift increases the random inbreeding rate and, consequently, the genetic load. This was confirmed by a significant correlation observed between the incidence of autosomal recessive hereditary diseases and mtDNA haplotype diversity. Based on the findings, mtDNA was assumed to provide an informative genetic system for genetic ecological monitoring; e. g., analyzing the ecology-driven changes in the gene pool. © 2011 Pleiades Publishing, Ltd.

Stolk L.,Erasmus University Rotterdam | Stolk L.,Netherlands Consortium of Healthy Aging | Perry J.R.B.,University of Exeter | Perry J.R.B.,University of Oxford | And 225 more authors.
Nature Genetics | Year: 2012

To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural menopause (at P < 5 - 10 g8). Candidate genes located at these newly associated loci include genes implicated in DNA repair (EXO1, HELQ, UIMC1, FAM175A, FANCI, TLK1, POLG and PRIM1) and immune function (IL11, NLRP11 and PRRC2A (also known as BAT2)). Gene-set enrichment pathway analyses using the full GWAS data set identified exoDNase, NF-I °B signaling and mitochondrial dysfunction as biological processes related to timing of menopause. © 2012 Nature America, Inc. All rights reserved.

Ellinor P.T.,Massachusetts General Hospital | Lunetta K.L.,Boston University | Lunetta K.L.,Lung and Blood Institutes Framingham Heart Study | Glazer N.L.,University of Washington | And 86 more authors.
Nature Genetics | Year: 2010

Atrial fibrillation (AF) is the most common sustained arrhythmia. Previous studies have identified several genetic loci associated with typical AF. We sought to identify common genetic variants underlying lone AF. This condition affects a subset of individuals without overt heart disease and with an increased heritability of AF. We report a meta-analysis of genome-wide association studies conducted using 1,335 individuals with lone AF (cases) and 12,844 unaffected individuals (referents). Cases were obtained from the German AF Network, Heart and Vascular Health Study, the Atherosclerosis Risk in Communities Study, the Cleveland Clinic and Massachusetts General Hospital. We identified an association on chromosome 1q21 to lone AF (rs13376333, adjusted odds ratio = 1.56; P = 6.3 × 10 12), and we replicated this association in two independent cohorts with lone AF (overall combined odds ratio = 1.52, 95% CI 1.40-1.64; P = 1.83 × 10 21). rs13376333 is intronic to KCNN3, which encodes a potassium channel protein involved in atrial repolarization. © 2010 Nature America, Inc. All rights reserved.

Utevska O.M.,University of Kharkiv | Pshenichnov A.S.,Research Center for Medical Genetics | Dibirova K.D.,Research Center for Medical Genetics | Rootsi S.,Estonian Biocenter | And 5 more authors.
Cytology and Genetics | Year: 2015

Results from studying Y-chromosomal polymorphisms of Russian and Ukrainian populations are presented for Slobozhanshina, which is a contemporary border region, inhabited in the 17th–18th centuries at the “Wild Field” boundary due to migrations of both the Russians from the north and Ukrainians from the west. In general, the Ukrainian and Russian populations of Slobozhanshchina are very close genetically; their set and frequency range of Y-chromosome haplogroups are typical for Eastern Europe. However, a detailed analysis of highly informative Y-chromosome markers showed that both nations retain the ethnic specificity of their gene pools after 3.5 centuries of coexistence in the same historical territory: the Ukrainian populations are similar to the rest of Ukraine, and Russian populations gravitate towards the south of European Russia. The persistent genetic differences may be due to the spatial characteristics of marriage migration and the predominant ethnic environment. © 2015, Allerton Press, Inc.

The indigenous inhabitants of the Andaman Islands were considered by many early anthropologists to be pristine examples of a "negrito" substrate of humanity that existed throughout Southeast Asia. Despite over 150 years of research and study, questions over the extent of shared ancestry between Andaman Islanders and other small-bodied, gracile, dark-skinned populations throughout the region are still unresolved. This shared phenotype could be a product of shared history, evolutionary convergence, or a mixture of both. Recent population genetic studies have tended to emphasize long-term physical isolation of the Andaman Islanders and an affinity to ancestral populations of South Asia. We reexamine the genetic evidence from genome-wide autosomal single-nucleotide polymorphism (SNP) data for a shared history between the tribes of Little Andaman (Onge) and Great Andaman, and between these two groups and the rest of South and Southeast Asia (both negrito and non-negrito groups). © 2013 Wayne State University Press.

News Article | September 22, 2016
Site: news.yahoo.com

Researchers have found that Aboriginal Australians are some of the oldest living populations on Earth. Here, Eske Willerslev talks to Aboriginal elders n the Kalgoorlie area in southwestern Australia in 2012. A group of humans migrating out of Africa some 40,000 to 70,000 years ago mingled with an as-yet unknown branch of humanity, researchers say. Modern humans originated about 150,000 to 200,000 years ago in Africa. However, scientists have long debated when and how the modern human lineage spread out of Africa to nearly every corner of the globe. Nearly everyone outside Africa descended from an exodus that occurred between 40,000 and 70,000 years ago, but recent archaeological findings and climate models suggest that migrations of modern humans from Africa began at least 100,000 years ago. One way to find out whether, in the past, modern humans dispersed from Africa in one wave or many — and to see if they intermingled with any other human lineages along the way — is to examine the genomes of present-day modern humans. [See Photos of Our Closest Human Ancestor] "We're interested in understanding how our species has come to be how it is through the lens of ancient DNA," said Swapan Mallick, bioinformatics director at Harvard Medical School in Boston and lead author of one of the three studies appearing in the Sept. 22 issue of the journal Nature. Previous human genetic databases often sampled a relatively narrow range of populations, which could skew results or miss key details about the migrations of modern humans out of Africa. Now, three studies have collected new, high-quality data from 787 human genomes from more than 280 geographically diverse populations around the world, including typically understudied and rapidly disappearing groups. Among the understudied groups researchers looked at are African populations, which have considerable genetic, linguistic and cultural diversity. They also examined genomes from Australia, where previous research uncovered some of the earliest archaeological and fossil evidence of modern humans outside Africa. The genetic analyses revealed the genomes of present-day aboriginal Australians might harbor evidence of ancient interbreeding with an unknown human lineage. "Who these people are, we don't know," said Eske Willerslev at the University of Copenhagen in Denmark, and senior author of one of the three studies. Previous research unearthed bones from a mysterious extinct branch of the human family tree from Denisova cave in Siberia's Altai Mountains. Analysis of DNA extracted from the fossils suggested these "Denisovans" shared a common origin with Neanderthals, but were nearly as genetically distinct from Neanderthals as Neanderthals were from living people. [Denisovan Gallery: Tracing the Genetics of Human Ancestors] Recent work suggested that Denisovans have contributed about 5 percent of their DNA to the genomes of present-day people of the Pacific islands of Oceania. However, these new findings suggest that what seemed to be evidence of Denisovans in the Pacific were actually signs of an unknown human lineage. "These guys were very distantly related to Denisovans, but by no means Denisovan," Willerslev told Live Science. "They were even more distantly related to Neanderthals, and they might have been even more distantly related to modern humans. We believe that they interbred with modern humans shortly before modern humans crossed into the ancient continent of Sahul — what is now Australia, New Guinea and Tasmania — some 50,000 to 60,000 years ago." The new findings also shed light on the controversy over whether modern humans dispersed from Africa in a single exodus or in multiple distinct waves at different times. When it came to people from Papua New Guinea, "we could discover, in the genomes of the Papuan individuals analyzed here, small traces of an additional, early expansion out of Africa that was previously hypothesized only from archaeological remains," Mait Metspalu, an evolutionary geneticist at the Estonian Biocenter in Tartu, Estonia, and senior author of one of the three studies, told Live Science. The researchers suggest that at least 2 percent of the Papuan genome harbors traces of an early migration that happened about 120,000 years ago. Previous research suggested that non-Africans largely descend from an exodus that happened between 40,000 and 70,000 years ago. "Our results, while for the most part confirming the already accepted model of a single expansion out of Africa as the source event of all non-African populations, show that additional expansions were not as unlikely as we thought," Luca Pagani, a molecular anthropologist at the Estonian Biocenter and lead author of one of the three studies, told Live Science. The scientists also discovered that aboriginal Australians "are one of the oldest living populations on Earth, and have been in the same area for the past 50,000 to 60,000 years," Willerslev said. There was a great deal of controversy "over whether or not aboriginal Australians directly descend from the first humans entering Australia," Willerslev said. "The answer to that question is yes — our data is completely consistent with aboriginal Australians descending from the first humans to enter Australia. It shows a very long connection between those people and the land. [How Did Life Arise on Earth] "I can't think of any other place in the world where humans have been so long in the same spot as Australia," Willerslev said. "Yes, there are populations in Africa that are older, but we have no idea if they stayed in the same area in Africa for as long a time." This is the first comprehensive population-level whole-genome study of human genetic diversity in Australia. "We found that because aboriginal Australians have spent such a long time in Australia, they are very genetically diverse," Willerslev said. "An aboriginal Australian from eastern Australia and one from southwestern Australia are almost as different genetically as an Asian is from a European." The researchers noted that about 90 percent of aboriginal Australians speak languages belonging to a single linguistic family, "but some people in northwest Australia speak other language families," Willerslev said. "It'd be very interesting to see what the story is there when it comes to how they migrated to Australia." In Photos: New Human Relative Shakes Up Our Family Tree Copyright 2016 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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