4 research outputs found
Geographic population structure analysis of worldwide human populations infers their biogeographical origins
The search for a method that utilizes biological information to predict humans’ place of origin has occupied scientists for millennia. Over the past four decades, scientists have employed genetic data in an effort to achieve this goal but with limited success. While biogeographical algorithms using next-generation sequencing data have achieved an accuracy of 700 km in Europe, they were inaccurate elsewhere. Here we describe the Geographic Population Structure (GPS) algorithm and demonstrate its accuracy with three data sets using 40,000–130,000 SNPs. GPS placed 83% of worldwide individuals in their country of origin. Applied to over 200 Sardinians villagers, GPS placed a quarter of them in their villages and most of the rest within 50 km of their villages. GPS’s accuracy and power to infer the biogeography of worldwide individuals down to their country or, in some cases, village, of origin, underscores the promise of admixture-based methods for biogeography and has ramifications for genetic ancestry testing
The GenoChip: A New Tool for Genetic Anthropology
The Genographic Project is an international effort aimed at charting human migratory history. The project is nonprofit and nonmedical,
and, through its Legacy Fund, supports locally led efforts to preserve indigenous and traditional cultures. Although the first
phase of the project was focused on uniparentally inherited markers on the Y-chromosome and mitochondrial DNA (mtDNA), the
current phase focuses on markers from across the entire genome to obtain a more complete understanding of human genetic
variation. Although many commercial arrays exist for genome-wide single-nucleotide polymorphism (SNP) genotyping, they were
designed for medical genetic studies and contain medically related markers that are inappropriate for global population genetic
studies. GenoChip, the Genographic Project’s new genotyping array, was designed to resolve these issues and enable higher resolution
research into outstanding questions in genetic anthropology. TheGenoChip includes ancestry informativemarkers obtained
for over 450 human populations, an ancient human (Saqqaq), and two archaic hominins (Neanderthal and Denisovan) and was
designed to identify all knownY-chromosome andmtDNAhaplogroups. The chip was carefully vetted to avoid inclusion ofmedically
relevant markers. To demonstrate its capabilities, we compared the FST distributions of GenoChip SNPs to those of two commercial
arrays. Although all arrays yielded similarly shaped (inverse J) FST distributions, the GenoChip autosomal and X-chromosomal distributions
had the highestmean FST, attesting to its ability to discern subpopulations. The chip performances are illustrated in a principal
component analysis for 14 worldwide populations. In summary, the GenoChip is a dedicated genotyping platform for genetic
anthropology. With an unprecedented number of approximately 12,000 Y-chromosomal and approximately 3,300 mtDNA SNPs
and over 130,000 autosomal and X-chromosomal SNPswithout any known health,medical, or phenotypic relevance, the GenoChip
is a useful tool for genetic anthropology and population genetics
The Requirements of Community: An Online Survey of the Social Work Access Network (Swan)
This study details the typical user profile of visitors to the Social Work Access Network (SWAN) website. The online survey methodology is discussed along with data that benchmarks expected response rates for this method. User preferences for additional content and interactive opportunities as well as user satisfaction with the current site are described. It is concluded that the social work professionals must seek new ways to define, organize and implement a portal on the World Wide Web by building partnerships among sites offering social work content. In support of this, SWAN must evolve to provide a platform for discussion among the social work community through online gatherings using chat and bulletin board technologies. © 2000 by The Haworth Press, Inc. All rights reserved
Y-chromosome analysis reveals genetic divergence and new founding native lineages in Athapaskan- and Eskimoan-speaking populations
University of Adelaide consortium members: Christina J. Adler, Alan Cooper, Clio S. I. Der Sarkissian, Wolfgang Haak.For decades, the peopling of the Americas has been explored through the analysis of uniparentally inherited genetic systems in Native American populations and the comparison of these genetic data with current linguistic groupings. In northern North America, two language families predominate: Eskimo-Aleut and Na-Dene. Although the genetic evidence from nuclear and mtDNA loci suggest that speakers of these language families share a distinct biological origin, this model has not been examined using data from paternally inherited Y chromosomes. To test this hypothesis and elucidate the migration histories of Eskimoan- and Athapaskan-speaking populations, we analyzed Y-chromosomal data from Inuvialuit, Gwich’in, and Tłįchǫ populations living in the Northwest Territories of Canada. Over 100 biallelic markers and 19 chromosome short tandem repeats (STRs) were genotyped to produce a high-resolution dataset of Y chromosomes from these groups. Among these markers is an SNP discovered in the Inuvialuit that differentiates them from other Aboriginal and Native American populations. The data suggest that Canadian Eskimoan- and Athapaskan-speaking populations are genetically distinct from one another and that the formation of these groups was the result of two population expansions that occurred after the initial movement of people into the Americas. In addition, the population history of Athapaskan speakers is complex, with the Tłįchǫ being distinct from other Athapaskan groups. The high-resolution biallelic data also make clear that Y-chromosomal diversity among the first Native Americans was greater than previously recognized.Matthew C. Dulik, Amanda C. Owings, Jill B. Gaieski, Miguel G. Vilar, Alestine Andre, Crystal Lennie, Mary Adele Mackenzie, Ingrid Kritsch, Sharon Snowshoe, Ruth Wright, James Martin, Nancy Gibson, Thomas D. Andrews, Theodore G. Schurr, and The Genographic Consortiu