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Sample records for african continental ancestry group

  1. Characterizing the admixed African ancestry of African Americans

    OpenAIRE

    Zakharia, Fouad; Basu, Analabha; Absher, Devin; Assimes, Themistocles L.; Go, Alan S.; Hlatky, Mark A.; Iribarren, Carlos; Knowles, Joshua W.; Li, Jun; Narasimhan, Balasubramanian; Sidney, Steven; Southwick, Audrey; Myers, Richard M.; Quertermous, Thomas; Risch, Neil

    2009-01-01

    Abstract Background Accurate, high-throughput genotyping allows the fine characterization of genetic ancestry. Here we applied recently developed statistical and computational techniques to the question of African ancestry in African Americans by using data on more than 450,000 single-nucleotide polymorphisms (SNPs) genotyped in 94 Africans of diverse geographic origins included in the...

  2. Effects of cis and trans genetic ancestry on gene expression in African Americans.

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    Alkes L Price

    2008-12-01

    Full Text Available Variation in gene expression is a fundamental aspect of human phenotypic variation. Several recent studies have analyzed gene expression levels in populations of different continental ancestry and reported population differences at a large number of genes. However, these differences could largely be due to non-genetic (e.g., environmental effects. Here, we analyze gene expression levels in African American cell lines, which differ from previously analyzed cell lines in that individuals from this population inherit variable proportions of two continental ancestries. We first relate gene expression levels in individual African Americans to their genome-wide proportion of European ancestry. The results provide strong evidence of a genetic contribution to expression differences between European and African populations, validating previous findings. Second, we infer local ancestry (0, 1, or 2 European chromosomes at each location in the genome and investigate the effects of ancestry proximal to the expressed gene (cis versus ancestry elsewhere in the genome (trans. Both effects are highly significant, and we estimate that 12+/-3% of all heritable variation in human gene expression is due to cis variants.

  3. Recent admixture in an Indian population of African ancestry.

    Science.gov (United States)

    Narang, Ankita; Jha, Pankaj; Rawat, Vimal; Mukhopadhyay, Arijit; Mukhopadhayay, Arijit; Dash, Debasis; Basu, Analabha; Mukerji, Mitali

    2011-07-15

    Identification and study of genetic variation in recently admixed populations not only provides insight into historical population events but also is a powerful approach for mapping disease loci. We studied a population (OG-W-IP) that is of African-Indian origin and has resided in the western part of India for 500 years; members of this population are believed to be descendants of the Bantu-speaking population of Africa. We have carried out this study by using a set of 18,534 autosomal markers common between Indian, CEPH-HGDP, and HapMap populations. Principal-components analysis clearly revealed that the African-Indian population derives its ancestry from Bantu-speaking west-African as well as Indo-European-speaking north and northwest Indian population(s). STRUCTURE and ADMIXTURE analyses show that, overall, the OG-W-IPs derive 58.7% of their genomic ancestry from their African past and have very little inter-individual ancestry variation (8.4%). The extent of linkage disequilibrium also reveals that the admixture event has been recent. Functional annotation of genes encompassing the ancestry-informative markers that are closer in allele frequency to the Indian ancestral population revealed significant enrichment of biological processes, such as ion-channel activity, and cadherins. We briefly examine the implications of determining the genetic diversity of this population, which could provide opportunities for studies involving admixture mapping. PMID:21737057

  4. Genetic Ancestry-Smoking Interactions and Lung Function in African Americans: A Cohort Study

    OpenAIRE

    Aldrich, Melinda C.; Kumar, Rajesh; Colangelo, Laura A.; Williams, L. Keoki; Sen, Saunak; Kritchevsky, Stephen B.; Meibohm, Bernd; Galanter, Joshua; Hu, Donglei; Gignoux, Christopher R.; Liu, Yongmei; Harris, Tamara B.; Ziv, Elad; Zmuda, Joseph; Garcia, Melissa

    2012-01-01

    Background Smoking tobacco reduces lung function. African Americans have both lower lung function and decreased metabolism of tobacco smoke compared to European Americans. African ancestry is also associated with lower pulmonary function in African Americans. We aimed to determine whether African ancestry modifies the association between smoking and lung function and its rate of decline in African Americans. Methodology/Principal Findings We evaluated a prospective ongoing cohort of 1,281 Afr...

  5. Afro-derived Amazonian populations: inferring continental ancestry and population substructure.

    Science.gov (United States)

    Lopes Maciel, Luana Gomes; Ribeiro Rodrigues, Elzemar Martins; Carneiro Dos Santos, Ney Pereira; Ribeiro Dos Santos, Ândrea; Guerreiro, João Farias; Santos, Sidney

    2011-10-01

    A panel of Ancestry Informative Markers (AIMs) was used to identify population substructure and estimate individual and overall interethnic admixture in 294 individuals from seven African-derived communities of the Brazilian Amazon. A panel of 48 biallelic markers, representing the insertion (IN) or the deletion (DEL) of small DNA fragments, was employed for this purpose. Overall interethnic admixture estimates showed high miscegenation with other ethnic groups in all populations (between 46% and 64%). The proportion of ancestral genes varied significantly among individuals of the sample: the contribution of African genes varied between 12% and 75%; of European genes between 10% and 73%; and of Amerindians genes between 8% and 66%. The obtained data reveal a high contribution of Amerindian genes in these communities, unlike in other African-derived communities of the Northeast and the South of Brazil. In addition, the majority of the Amerindian contribution may result from the preferential inclusion of indigenous women in the African descent groups. High heterogeneity of the proportion of interethnic admixture among analyzed individuals was found when the proportion of ancestral genes of each individual of the sample was estimated. This heterogeneity is reflected in the fact that four populations can be considered as substructured and that the global African descent sample is possibly formed by two subpopulations. PMID:22146065

  6. Lactase persistence alleles reveal partial East African ancestry of southern African Khoe pastoralists.

    Science.gov (United States)

    Breton, Gwenna; Schlebusch, Carina M; Lombard, Marlize; Sjödin, Per; Soodyall, Himla; Jakobsson, Mattias

    2014-04-14

    The ability to digest milk into adulthood, lactase persistence (LP), as well as specific genetic variants associated with LP, is heterogeneously distributed in global populations. These variants were most likely targets of selection when some populations converted from hunter-gatherer to pastoralist or farming lifestyles. Specific LP polymorphisms are associated with particular geographic regions and populations; however, they have not been extensively studied in southern Africa. We investigate the LP-regulatory region in 267 individuals from 13 southern African populations (including descendants of hunter-gatherers, pastoralists, and agropastoralists), providing the first comprehensive study of the LP-regulatory region in a large group of southern Africans. The "East African" LP single-nucleotide polymorphism (SNP) (14010G>C) was found at high frequency (>20%) in a strict pastoralist Khoe population, the Nama of Namibia, suggesting a connection to East Africa, whereas the "European" LP SNP (13910C>T) was found in populations of mixed ancestry. Using genome-wide data from various African populations, we identify admixture (13%) in the Nama, from an Afro-Asiatic group dating to >1,300 years ago, with the remaining fraction of their genomes being from San hunter-gatherers. We also find evidence of selection around the LCT gene among Khoe-speaking groups, and the substantial frequency of the 14010C variant among the Nama is best explained by adaptation to digesting milk. These genome-local and genome-wide results support a model in which an East African group brought pastoralist practices to southern Africa and admixed with local hunter-gatherers to form the ancestors of Khoe people. PMID:24704072

  7. Identification, replication, and fine-mapping of Loci associated with adult height in individuals of african ancestry.

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    Amidou N'Diaye

    2011-10-01

    Full Text Available Adult height is a classic polygenic trait of high heritability (h(2 approximately 0.8. More than 180 single nucleotide polymorphisms (SNPs, identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain approximately10% of the variance in height. Discovery efforts in other populations, while limited, have revealed loci for height not previously implicated in individuals of European ancestry. Here, we performed a meta-analysis of genome-wide association (GWA results for adult height in 20,427 individuals of African ancestry with replication in up to 16,436 African Americans. We found two novel height loci (Xp22-rs12393627, P = 3.4×10(-12 and 2p14-rs4315565, P = 1.2×10(-8. As a group, height associations discovered in European-ancestry samples replicate in individuals of African ancestry (P = 1.7×10(-4 for overall replication. Fine-mapping of the European height loci in African-ancestry individuals showed an enrichment of SNPs that are associated with expression of nearby genes when compared to the index European height SNPs (P<0.01. Our results highlight the utility of genetic studies in non-European populations to understand the etiology of complex human diseases and traits.

  8. Paraoxonase1 Genetic Polymorphisms in a Mixed Ancestry African Population

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    M. Macharia

    2014-01-01

    Full Text Available Paraoxonase 1 (PON1 activity is markedly influenced by coding polymorphisms, Q/R at position 192 and M/L at position 55 of the PON1 gene. We investigated the frequencies of these polymorphisms and their effects on PON1 and antioxidant activities in 844 South African mixed ancestry individuals. Genotyping was done using allele-specific TaqMan technology, PON1 activities were measured using paraoxon and phenylacetate, oxidative status was determined by measuring the antioxidant activities of ferric reducing antioxidant power and trolox equivalent antioxidant capacity, and lipid peroxidation markers included malondialdehyde and oxidized LDL. The frequencies of Q192R and L55M were 47.6% and 28.8%, respectively, and the most common corresponding alleles were 192R (60.4% and 55M (82.6%. The Q192 was significantly associated with 5.8 units’ increase in PON1 concentration and 15.4 units’ decrease in PONase activity after adjustment for age, sex, BMI, and diabetes, with suggestion of differential effects by diabetes status. The PON1 L55 variant was associated with none of the measured indices. In conclusion, we have shown that the Q192R polymorphism is a determinant of both PON1 concentration and activity and this association appeared to be enhanced in subjects with diabetes.

  9. A SNP test to identify Africanized honeybees via proportion of 'African' ancestry.

    Science.gov (United States)

    Chapman, Nadine C; Harpur, Brock A; Lim, Julianne; Rinderer, Thomas E; Allsopp, Michael H; Zayed, Amro; Oldroyd, Benjamin P

    2015-11-01

    The honeybee, Apis mellifera, is the world's most important pollinator and is ubiquitous in most agricultural ecosystems. Four major evolutionary lineages and at least 24 subspecies are recognized. Commercial populations are mainly derived from subspecies originating in Europe (75-95%). The Africanized honeybee is a New World hybrid of A. m. scutellata from Africa and European subspecies, with the African component making up 50-90% of the genome. Africanized honeybees are considered undesirable for bee-keeping in most countries, due to their extreme defensiveness and poor honey production. The international trade in honeybees is restricted, due in part to bans on the importation of queens (and semen) from countries where Africanized honeybees are extant. Some desirable strains from the United States of America that have been bred for traits such as resistance to the mite Varroa destructor are unfortunately excluded from export to countries such as Australia due to the presence of Africanized honeybees in the USA. This study shows that a panel of 95 single nucleotide polymorphisms, chosen to differentiate between the African, Eastern European and Western European lineages, can detect Africanized honeybees with a high degree of confidence via ancestry assignment. Our panel therefore offers a valuable tool to mitigate the risks of spreading Africanized honeybees across the globe and may enable the resumption of queen and bee semen imports from the Americas. PMID:25846634

  10. Differences in optic nerve structure between individuals of predominantly African and European ancestry: Implications for disease detection and pathogenesis

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    Christopher A Girkin

    2008-03-01

    Full Text Available Christopher A GirkinUniversity of Alabama at Birmingham School of Medicine, Birmingham, AL, USAAbstract: Glaucoma disproportionately affects individual of African ancestry. Additionally, racial differences in the optic nerve head have been well described that may alter the vulnerability to intraocular pressure related injury and, in addition, alter the clinical ability to detect the presence of early optic nerve injury. This paper will review the literature describing racial differences in the optic nerve head between individuals of African and European ancestry with regards to the potential effects of these differences on the ability to detect glaucoma in different racial groups and to potential differences in the pathogenesis of glaucomatous injury.Keywords: primary open angle glaucoma, African American, optic nerve, optic disc, retinal nerve fiber layer

  11. Multiplex genotyping system for efficient inference of matrilineal genetic ancestry with continental resolution

    OpenAIRE

    van Oven Mannis; Vermeulen Mark; Kayser Manfred

    2011-01-01

    Abstract Background In recent years, phylogeographic studies have produced detailed knowledge on the worldwide distribution of mitochondrial DNA (mtDNA) variants, linking specific clades of the mtDNA phylogeny with certain geographic areas. However, a multiplex genotyping system for the detection of the mtDNA haplogroups of major continental distribution that would be desirable for efficient DNA-based bio-geographic ancestry testing in various applications is still missing. Results Three mult...

  12. Multiplex genotyping system for efficient inference of matrilineal genetic ancestry with continental resolution

    Directory of Open Access Journals (Sweden)

    van Oven Mannis

    2011-03-01

    Full Text Available Abstract Background In recent years, phylogeographic studies have produced detailed knowledge on the worldwide distribution of mitochondrial DNA (mtDNA variants, linking specific clades of the mtDNA phylogeny with certain geographic areas. However, a multiplex genotyping system for the detection of the mtDNA haplogroups of major continental distribution that would be desirable for efficient DNA-based bio-geographic ancestry testing in various applications is still missing. Results Three multiplex genotyping assays, based on single-base primer extension technology, were developed targeting a total of 36 coding-region mtDNA variants that together differentiate 43 matrilineal haplo-/paragroups. These include the major diagnostic haplogroups for Africa, Western Eurasia, Eastern Eurasia and Native America. The assays show high sensitivity with respect to the amount of template DNA: successful amplification could still be obtained when using as little as 4 pg of genomic DNA and the technology is suitable for medium-throughput analyses. Conclusions We introduce an efficient and sensitive multiplex genotyping system for bio-geographic ancestry inference from mtDNA that provides resolution on the continental level. The method can be applied in forensics, to aid tracing unknown suspects, as well as in population studies, genealogy and personal ancestry testing. For more complete inferences of overall bio-geographic ancestry from DNA, the mtDNA system provided here can be combined with multiplex systems for suitable autosomal and, in the case of males, Y-chromosomal ancestry-sensitive DNA markers.

  13. A genome-wide association study of breast cancer in women of African ancestry

    OpenAIRE

    Chen, Fang; Chen, Gary K.; Stram, Daniel O.; Millikan, Robert C.; Ambrosone, Christine B.; John, Esther M; Bernstein, Leslie; Zheng, Wei; Palmer, Julie R.; Jennifer J Hu; Rebbeck, Tim R.; Ziegler, Regina G.; Nyante, Sarah; Bandera, Elisa V.; Sue A Ingles

    2012-01-01

    Genome-wide association studies (GWAS) in diverse populations are needed to reveal variants that are more common and/or limited to defined populations. We conducted a GWAS of breast cancer in women of African ancestry, with genotyping of > 1,000,000 SNPs in 3,153 African American cases and 2,831 controls, and replication testing of the top 66 associations in an additional 3,607 breast cancer cases and 11,330 controls of African ancestry. Two of the 66 SNPs replicated (p < 0.05) in stage 2, wh...

  14. Validation of two prediction models of undiagnosed chronic kidney disease in mixed-ancestry South Africans

    OpenAIRE

    Mogueo, Amelie; Echouffo-Tcheugui, Justin B; Matsha, Tandi E.; Erasmus, Rajiv T; Kengne, Andre P.

    2015-01-01

    Background Chronic kidney disease (CKD) is a global challenge. Risk models to predict prevalent undiagnosed CKD have been published. However, none was developed or validated in an African population. We validated the Korean and Thai CKD prediction model in mixed-ancestry South Africans. Methods Discrimination and calibration were assessed overall and by major subgroups. CKD was defined as ‘estimated glomerular filtration rate (eGFR)

  15. Genetic ancestry, self-reported race and ethnicity in African Americans and European Americans in the PCaP cohort.

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    Lara E Sucheston

    Full Text Available BACKGROUND: Family history and African-American race are important risk factors for both prostate cancer (CaP incidence and aggressiveness. When studying complex diseases such as CaP that have a heritable component, chances of finding true disease susceptibility alleles can be increased by accounting for genetic ancestry within the population investigated. Race, ethnicity and ancestry were studied in a geographically diverse cohort of men with newly diagnosed CaP. METHODS: Individual ancestry (IA was estimated in the population-based North Carolina and Louisiana Prostate Cancer Project (PCaP, a cohort of 2,106 incident CaP cases (2063 with complete ethnicity information comprising roughly equal numbers of research subjects reporting as Black/African American (AA or European American/Caucasian/Caucasian American/White (EA from North Carolina or Louisiana. Mean genome wide individual ancestry estimates of percent African, European and Asian were obtained and tested for differences by state and ethnicity (Cajun and/or Creole and Hispanic/Latino using multivariate analysis of variance models. Principal components (PC were compared to assess differences in genetic composition by self-reported race and ethnicity between and within states. RESULTS: Mean individual ancestries differed by state for self-reporting AA (p = 0.03 and EA (p = 0.001. This geographic difference attenuated for AAs who answered "no" to all ethnicity membership questions (non-ethnic research subjects; p = 0.78 but not EA research subjects, p = 0.002. Mean ancestry estimates of self-identified AA Louisiana research subjects for each ethnic group; Cajun only, Creole only and both Cajun and Creole differed significantly from self-identified non-ethnic AA Louisiana research subjects. These ethnicity differences were not seen in those who self-identified as EA. CONCLUSIONS: Mean IA differed by race between states, elucidating a potential contributing factor to these differences in AA

  16. Blood group genotyping in a population of highly diverse ancestry.

    Science.gov (United States)

    Pellegrino, J; Castilho, L; Rios, M; De Souza, C A

    2001-01-01

    Accurate phenotyping of red blood cells (RBCs) can be difficult in transfusion-dependent patients such as those with thalassemia and sickle cell anemia because of the presence of previously transfused RBCs in the patient's circulation. Recently, the molecular basis associated with the expression of many blood group antigens was established. This allowed the development of a plethora of polymerase chain reaction (PCR)-based tests for identification of the blood group antigens by testing DNA. The new technologies complement phenotyping and overcome some of the limitations of hemagglutination assays. These molecular assays were developed on the basis of DNA sequences of individuals of Caucasian ancestry. The present study addresses the concern that these genotyping assays may not be applicable to populations of highly diverse ancestry because of variability in intronic regions or because of unrecognized alleles. We determined both phenotype and genotype for RH D, K 1/K 2, JK A/JK B, FY A/ FY B-GATA in 250 normal blood donors using PCR. Phenotype and genotype results agreed in 100% of the cases, indicating that molecular genotyping protocols can be effectively applied to populations with a highly diverse genetic background. However, genotyping for Duffy antigens provided information that could not be obtained by phenotyping. Essentially, 30.5 % of the donors with the FY B gene typed as Fy(b-) because of mutations in the GATA box. This information is very useful for the management of transfusion dependent patients. PMID:11170227

  17. A meta-analysis identifies new loci associated with body mass index in individuals of African ancestry

    NARCIS (Netherlands)

    Monda, Keri L.; Chen, Gary K.; Taylor, Kira C.; Palmer, Cameron; Edwards, Todd L.; Lange, Leslie A.; Ng, Maggie C. Y.; Adeyemo, Adebowale A.; Allison, Matthew A.; Bielak, Lawrence F.; Chen, Guanjie; Graff, Mariaelisa; Irvin, Marguerite R.; Rhie, Suhn K.; Li, Guo; Liu, Yongmei; Liu, Youfang; Lu, Yingchang; Nalls, Michael A.; Sun, Yan V.; Wojczynski, Mary K.; Yanek, Lisa R.; Aldrich, Melinda C.; Ademola, Adeyinka; Amos, Christopher I.; Bandera, Elisa V.; Bock, Cathryn H.; Britton, Angela; Broeckel, Ulrich; Cai, Quiyin; Caporaso, Neil E.; Carlson, Chris S.; Carpten, John; Casey, Graham; Chen, Wei-Min; Chen, Fang; Chen, Yii-Der I.; Chiang, Charleston W. K.; Coetzee, Gerhard A.; Demerath, Ellen; Deming-Halverson, Sandra L.; Driver, Ryan W.; Dubbert, Patricia; Feitosa, Mary F.; Feng, Ye; Freedman, Barry I.; Gillanders, Elizabeth M.; Gottesman, Omri; Guo, Xiuqing; Haritunians, Talin; Harris, Tamara; Harris, Curtis C.; Hennis, Anselm J. M.; Hernandez, Dena G.; McNeill, Lorna H.; Howard, Timothy D.; Howard, Barbara V.; Howard, Virginia J.; Johnson, Karen C.; Kang, Sun J.; Keating, Brendan J.; Kolb, Suzanne; Kuller, Lewis H.; Kutlar, Abdullah; Langefeld, Carl D.; Lettre, Guillaume; Lohman, Kurt; Lotay, Vaneet; Lyon, Helen; Manson, Joann E.; Maixner, William; Meng, Yan A.; Monroe, Kristine R.; Morhason-Bello, Imran; Murphy, Adam B.; Mychaleckyj, Josyf C.; Nadukuru, Rajiv; Nathanson, Katherine L.; Nayak, Uma; N'Diaye, Amidou; Nemesure, Barbara; Wu, Suh-Yuh; Leske, M. Cristina; Neslund-Dudas, Christine; Neuhouser, Marian; Nyante, Sarah; Ochs-Balcom, Heather; Ogunniyi, Adesola; Ogundiran, Temidayo O.; Ojengbede, Oladosu; Olopade, Olufunmilayo I.; Palmer, Julie R.; Ruiz-Narvaez, Edward A.; Palmer, Nicholette D.; Press, Michael F.; Rampersaud, Evandine; Rasmussen-Torvik, Laura J.; Rodriguez-Gil, Jorge L.; Salako, Babatunde; Schadt, Eric E.; Schwartz, Ann G.; Shriner, Daniel A.; Siscovick, David; Smith, Shad B.; Wassertheil-Smoller, Sylvia; Speliotes, Elizabeth K.; Spitz, Margaret R.; Sucheston, Lara; Taylor, Herman; Tayo, Bamidele O.; Tucker, Margaret A.; Van Den Berg, David J.; Edwards, Digna R. Velez; Wang, Zhaoming; Wiencke, John K.; Winkler, Thomas W.; Witte, John S.; Wrensch, Margaret; Wu, Xifeng; Yang, James J.; Levin, Albert M.; Young, Taylor R.; Zakai, Neil A.; Cushman, Mary; Zanetti, Krista A.; Zhao, Jing Hua; Zhao, Wei; Zheng, Yonglan; Zhou, Jie; Ziegler, Regina G.; Zmuda, Joseph M.; Fernandes, Jyotika K.; Gilkeson, Gary S.; Kamen, Diane L.; Hunt, Kelly J.; Spruill, Ida J.; Ambrosone, Christine B.; Ambs, Stefan; Arnett, Donna K.; Atwood, Larry; Becker, Diane M.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Borecki, Ingrid B.; Bottinger, Erwin P.; Bowden, Donald W.; Burke, Gregory; Chanock, Stephen J.; Cooper, Richard S.; Ding, Jingzhong; Duggan, David; Evans, Michele K.; Fox, Caroline; Garvey, W. Timothy; Bradfield, Jonathan P.; Hakonarson, Hakon; Grant, Struan F. A.; Hsing, Ann; Chu, Lisa; Hu, Jennifer J.; Huo, Dezheng; Ingles, Sue A.; John, Esther M.; Jordan, Joanne M.; Kabagambe, Edmond K.; Kardia, Sharon L. R.; Kittles, Rick A.; Goodman, Phyllis J.; Klein, Eric A.; Kolonel, Laurence N.; Le Marchand, Loic; Liu, Simin; McKnight, Barbara; Millikan, Robert C.; Mosley, Thomas H.; Padhukasahasram, Badri; Williams, L. Keoki; Patel, Sanjay R.; Peters, Ulrike; Pettaway, Curtis A.; Peyser, Patricia A.; Psaty, Bruce M.; Redline, Susan; Rotimi, Charles N.; Rybicki, Benjamin A.; Sale, Michele M.; Schreiner, Pamela J.; Signorello, Lisa B.; Singleton, Andrew B.; Stanford, Janet L.; Strom, Sara S.; Thun, Michael J.; Vitolins, Mara; Zheng, Wei; Moore, Jason H.; Williams, Scott M.; Ketkar, Shamika; Zhu, Xiaofeng; Zonderman, Alan B.; Kooperberg, Charles; Papanicolaou, George J.; Henderson, Brian E.; Reiner, Alex P.; Hirschhorn, Joel N.; Loos, Ruth J. F.; North, Kari E.; Haiman, Christopher A.

    2013-01-01

    Genome-wide association studies (GWAS) have identified 36 loci associated with body mass index (BMI), predominantly in populations of European ancestry. We conducted a meta-analysis to examine the association of >3.2 million SNPs with BMI in 39,144 men and women of African ancestry and followed up t

  18. African Ancestry Analysis and Admixture Genetic Mapping for Proliferative Diabetic Retinopathy in African Americans

    Science.gov (United States)

    Tandon, Arti; Chen, Ching J.; Penman, Alan; Hancock, Heather; James, Maurice; Husain, Deeba; Andreoli, Christopher; Li, Xiaohui; Kuo, Jane Z.; Idowu, Omolola; Riche, Daniel; Papavasilieou, Evangelia; Brauner, Stacey; Smith, Sataria O.; Hoadley, Suzanne; Richardson, Cole; Kieser, Troy; Vazquez, Vanessa; Chi, Cheryl; Fernandez, Marlene; Harden, Maegan; Cotch, Mary Frances; Siscovick, David; Taylor, Herman A.; Wilson, James G.; Reich, David; Wong, Tien Y.; Klein, Ronald; Klein, Barbara E. K.; Rotter, Jerome I.; Patterson, Nick; Sobrin, Lucia

    2015-01-01

    Purpose. To examine the relationship between proportion of African ancestry (PAA) and proliferative diabetic retinopathy (PDR) and to identify genetic loci associated with PDR using admixture mapping in African Americans with type 2 diabetes (T2D). Methods. Between 1993 and 2013, 1440 participants enrolled in four different studies had fundus photographs graded using the Early Treatment Diabetic Retinopathy Study scale. Cases (n = 305) had PDR while controls (n = 1135) had nonproliferative diabetic retinopathy (DR) or no DR. Covariates included diabetes duration, hemoglobin A1C, systolic blood pressure, income, and education. Genotyping was performed on the Affymetrix platform. The association between PAA and PDR was evaluated using logistic regression. Genome-wide admixture scanning was performed using ANCESTRYMAP software. Results. In the univariate analysis, PDR was associated with increased PAA (odds ratio [OR] = 1.36, 95% confidence interval [CI] = 1.16–1.59, P = 0.0002). In multivariate regression adjusting for traditional DR risk factors, income and education, the association between PAA and PDR was attenuated and no longer significant (OR = 1.21, 95% CI = 0.59–2.47, P = 0.61). For the admixture analyses, the maximum genome-wide score was 1.44 on chromosome 1. Conclusions. In this largest study of PDR in African Americans with T2D to date, an association between PAA and PDR is not present after adjustment for clinical, demographic, and socioeconomic factors. No genome-wide significant locus (defined as having a locus-genome statistic > 5) was identified with admixture analysis. Further analyses with even larger sample sizes are needed to definitively assess if any admixture signal for DR is present. PMID:26098467

  19. Comparison of genome-wide variation between Malawians and African ancestry HapMap populations.

    Science.gov (United States)

    Joubert, Bonnie R; North, Kari E; Wang, Yunfei; Mwapasa, Victor; Franceschini, Nora; Meshnick, Steven R; Lange, Ethan M

    2010-06-01

    Understanding genetic variation between populations is important because it affects the portability of human genome-wide analytical methods. We compared genetic variation and substructure between Malawians and other African and non-African HapMap populations. Allele frequencies and adjacent linkage disequilibrium (LD) were measured for 617 715 single nucleotide polymorphisms (SNPs) across subject genomes. Allele frequencies in the Malawian population (N=226) were highly correlated with allele frequencies in HapMap populations of African ancestry (AFA, N=376), namely Yoruban in Ibadan, Nigeria (Spearman's r(2)=0.97), Luhya in Webuye, Kenya (r(2)=0.97), African Americans in the southwest United States (r(2)=0.94) and Maasai in Kinyawa, Kenya (r(2)=0.91). This correlation was much lower between Malawians and other ancestry populations (r(2)0.82, other ancestries r(2)Maasai in Kenyawa, Kenya (rs3769013, rs730005, rs3769012, rs2304370; P-values <1 x 10(-33)). PMID:20485449

  20. Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci

    OpenAIRE

    Liu, Ching-Ti; Keri L Monda; Taylor, Kira C.; Lange, Leslie; Demerath, Ellen W; Palmas, Walter; Wojczynski, Mary K.; Jaclyn C Ellis; Mara Z Vitolins; Liu, Simin; Papanicolaou, George J.; Irvin, Marguerite R.; Xue, Luting; Griffin, Paula J.; Michael A Nalls

    2013-01-01

    Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in...

  1. A Meta-Analysis Identifies New Loci Associated with Body Mass index in Individuals of African Ancestry

    OpenAIRE

    Keri L Monda; Chen, Gary K.; Taylor, Kira C.; Palmer, Cameron; Edwards, Todd L.; Lange, Leslie A.; Ng, Maggie C. Y.; Adeyemo, Adebowale A.; Allison, Matthew A.; Bielak, Lawrence F; Chen, Guanji; Graff, Mariaelisa; Irvin, Marguerite R.; Rhie, Suhn K.; Li, Guo

    2013-01-01

    Genome-wide association studies (GWAS) have identified 36 loci associated with body mass index (BMI), predominantly in populations of European ancestry. We conducted a meta-analysis to examine the association of >3.2 million SNPs with BMI in 39,144 men and women of African ancestry, and followed up the most significant associations in an additional 32,268 individuals of African ancestry. We identified one novel locus at 5q33 (GALNT10, rs7708584, p=3.4×10−11) and another at 7p15 when combined ...

  2. Genetic association for renal traits among participants of African ancestry reveals new loci for renal function.

    Directory of Open Access Journals (Sweden)

    Ching-Ti Liu

    2011-09-01

    Full Text Available Chronic kidney disease (CKD is an increasing global public health concern, particularly among populations of African ancestry. We performed an interrogation of known renal loci, genome-wide association (GWA, and IBC candidate-gene SNP association analyses in African Americans from the CARe Renal Consortium. In up to 8,110 participants, we performed meta-analyses of GWA and IBC array data for estimated glomerular filtration rate (eGFR, CKD (eGFR 30 mg/g and interrogated the 250 kb flanking region around 24 SNPs previously identified in European Ancestry renal GWAS analyses. Findings were replicated in up to 4,358 African Americans. To assess function, individually identified genes were knocked down in zebrafish embryos by morpholino antisense oligonucleotides. Expression of kidney-specific genes was assessed by in situ hybridization, and glomerular filtration was evaluated by dextran clearance. Overall, 23 of 24 previously identified SNPs had direction-consistent associations with eGFR in African Americans, 2 of which achieved nominal significance (UMOD, PIP5K1B. Interrogation of the flanking regions uncovered 24 new index SNPs in African Americans, 12 of which were replicated (UMOD, ANXA9, GCKR, TFDP2, DAB2, VEGFA, ATXN2, GATM, SLC22A2, TMEM60, SLC6A13, and BCAS3. In addition, we identified 3 suggestive loci at DOK6 (p-value = 5.3×10(-7 and FNDC1 (p-value = 3.0×10(-7 for UACR, and KCNQ1 with eGFR (p = 3.6×10(-6. Morpholino knockdown of kcnq1 in the zebrafish resulted in abnormal kidney development and filtration capacity. We identified several SNPs in association with eGFR in African Ancestry individuals, as well as 3 suggestive loci for UACR and eGFR. Functional genetic studies support a role for kcnq1 in glomerular development in zebrafish.

  3. Genomic African and Native American Ancestry and Chagas Disease: The Bambui (Brazil) Epigen Cohort Study of Aging

    Science.gov (United States)

    2016-01-01

    Background The influence of genetic ancestry on Trypanosoma cruzi infection and Chagas disease outcomes is unknown. Methodology/Principal Findings We used 370,539 Single Nucleotide Polymorphisms (SNPs) to examine the association between individual proportions of African, European and Native American genomic ancestry with T. cruzi infection and related outcomes in 1,341 participants (aged ≥ 60 years) of the Bambui (Brazil) population-based cohort study of aging. Potential confounding variables included sociodemographic characteristics and an array of health measures. The prevalence of T. cruzi infection was 37.5% and 56.3% of those infected had a major ECG abnormality. Baseline T. cruzi infection was correlated with higher levels of African and Native American ancestry, which in turn were strongly associated with poor socioeconomic circumstances. Cardiomyopathy in infected persons was not significantly associated with African or Native American ancestry levels. Infected persons with a major ECG abnormality were at increased risk of 15-year mortality relative to their counterparts with no such abnormalities (adjusted hazard ratio = 1.80; 95% 1.41, 2.32). African and Native American ancestry levels had no significant effect modifying this association. Conclusions/Significance Our findings indicate that African and Native American ancestry have no influence on the presence of major ECG abnormalities and had no influence on the ability of an ECG abnormality to predict mortality in older people infected with T. cruzi. In contrast, our results revealed a strong and independent association between prevalent T. cruzi infection and higher levels of African and Native American ancestry. Whether this association is a consequence of genetic background or differential exposure to infection remains to be determined. PMID:27182885

  4. Screening for the beta-thalassaemia trait: hazards among populations of West African Ancestry

    OpenAIRE

    Gibson, Felicea; Mason, Karlene; Serjeant, Beryl; Kulozik, Andreas; Happich, Margit; Tolle, Gabriele; Hambleton, Ian; Serjeant, Graham

    2011-01-01

    The aim of this study was to examine the accuracy and characteristics of detecting the beta-thalassaemia trait in populations of West African ancestry. School children, aged 16–19 years, in Manchester Parish, Jamaica were screened to detect the genes which could give rise to offspring with sickle cell disease. Haematological indices and HbA2 levels in subjects with an MCH ≤ 26 pg and an RDW G in 19 (25%), −90 C>T in 7 (9%), the IVS II-849 A>G in 5 (6%) with smaller contributions from five oth...

  5. Estimates of Continental Ancestry Vary Widely among Individuals with the Same mtDNA Haplogroup

    OpenAIRE

    Emery, Leslie S.; Magnaye, Kevin M.; Bigham, Abigail W.; Akey, Joshua M.; Bamshad, Michael J.

    2015-01-01

    The association between a geographical region and an mtDNA haplogroup(s) has provided the basis for using mtDNA haplogroups to infer an individual’s place of origin and genetic ancestry. Although it is well known that ancestry inferences using mtDNA haplogroups and those using genome-wide markers are frequently discrepant, little empirical information exists on the magnitude and scope of such discrepancies between multiple mtDNA haplogroups and worldwide populations. We compared genetic-ances...

  6. Association between Plasma 25-Hydroxyvitamin D, Ancestry and Aggressive Prostate Cancer among African Americans and European Americans in PCaP.

    Directory of Open Access Journals (Sweden)

    Susan E Steck

    Full Text Available African Americans (AAs have lower circulating 25-hydroxyvitamin D3 [25(OHD3] concentrations and higher prostate cancer (CaP aggressiveness than other racial/ethnic groups. The purpose of the current study was to examine the relationship between plasma 25(OHD3, African ancestry and CaP aggressiveness among AAs and European Americans (EAs.Plasma 25(OHD3 was measured using LC-MS/MS (Liquid Chromatography Tandem Mass Spectrometry in 537 AA and 663 EA newly-diagnosed CaP patients from the North Carolina-Louisiana Prostate Cancer Project (PCaP classified as having either 'high' or 'low' aggressive disease based on clinical stage, Gleason grade and prostate specific antigen at diagnosis. Mean plasma 25(OHD3 concentrations were compared by proportion of African ancestry. Logistic regression was used to calculate multivariable adjusted odds ratios (OR and 95% confidence intervals (95%CI for high aggressive CaP by tertile of plasma 25(OHD3.AAs with highest percent African ancestry (>95% had the lowest mean plasma 25(OHD3 concentrations. Overall, plasma 25(OHD3 was associated positively with aggressiveness among AA men, an association that was modified by calcium intake (ORT 3vs.T1: 2.23, 95%CI: 1.26-3.95 among men with low calcium intake, and ORT 3vs.T1: 0.19, 95%CI: 0.05-0.70 among men with high calcium intake. Among EAs, the point estimates of the ORs were <1.0 for the upper tertiles with CIs that included the null.Among AAs, plasma 25(OHD3 was associated positively with CaP aggressiveness among men with low calcium intake and inversely among men with high calcium intake. The clinical significance of circulating concentrations of 25(OHD3 and interactions with calcium intake in the AA population warrants further study.

  7. Polymorphisms of Estrogen Metabolism-Related Genes and Prostate Cancer Risk in Two Populations of African Ancestry

    Science.gov (United States)

    Emeville, Elise; Ferdinand, Séverine; Punga, Augustin; Lufuma, Simon; Blanchet, Pascal; Romana, Marc; Multigner, Luc

    2016-01-01

    Background Estrogens are thought to play a critical role in prostate carcinogenesis. It has been suggested that polymorphisms of genes encoding enzymes involved in estrogen metabolism are risk factors for prostate cancer. However, few studies have been performed on populations of African ancestry, which are known to have a high risk of prostate cancer. Objective We investigated whether functional polymorphisms of CYP17, CYP19, CYP1B1, COMT and UGT1A1 affected the risk of prostate cancer in two different populations of African ancestry. Methods In Guadeloupe (French West Indies), we compared 498 prostate cancer patients and 565 control subjects. In Kinshasa (Democratic Republic of Congo), 162 prostate cancer patients were compared with 144 controls. Gene polymorphisms were determined by the SNaPshot technique or short tandem repeat PCR analysis. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Results The AA genotype and the A allele of rs4680 (COMT) appeared to be inversely associated with the risk of prostate cancer in adjusted models for both Afro-Caribbean and native African men. For the A allele, a significant inverse association was observed among cases with low-grade Gleason scores and localized clinical stage, in both populations. Conclusions These preliminary results support the hypothesis that polymorphisms of genes encoding enzymes involved in estrogen metabolism may modulate the risk of prostate cancer in populations of African ancestry. PMID:27074016

  8. From Continental Priorities to Local Conservation: A Multi-Level Analysis for African Tortoises

    OpenAIRE

    Pierluigi Bombi; Manuela D'Amen; Luca Luiselli

    2013-01-01

    Terrestrial tortoises are the most endangered group of vertebrates but they are still largely ignored for defining global conservation priorities. In this paper, we explored within a hierarchical framework the potential contribution of prioritization studies at the continental scale to the planning of local initiatives for the conservation of African tortoises at the regional level. First, we modeled the distribution of all the African tortoise species, we calculated three indicators of conse...

  9. Junctophilin 3 (JPH3) expansion mutations causing Huntington disease like 2 (HDL2) are common in South African patients with African ancestry and a Huntington disease phenotype.

    Science.gov (United States)

    Krause, Amanda; Mitchell, Claire; Essop, Fahmida; Tager, Susan; Temlett, James; Stevanin, Giovanni; Ross, Christopher; Rudnicki, Dobrila; Margolis, Russell

    2015-10-01

    Huntington disease (HD) is a progressive autosomal dominant neurodegenerative disorder, characterized by abnormal movements, cognitive decline, and psychiatric symptoms, caused by a CAG repeat expansion in the huntingtin (HTT) gene on chromosome 4p. A CAG/CTG repeat expansion in the junctophilin-3 (JPH3) gene on chromosome 16q24.2 causes a Huntington disease-like phenotype (HDL2). All patients to date with HDL2 have some African ancestry. The present study aimed to characterize the genetic basis of the Huntington disease phenotype in South Africans and to investigate the possible origin of the JPH3 mutation. In a sample of unrelated South African individuals referred for diagnostic HD testing, 62% (106/171) of white patients compared to only 36% (47/130) of black patients had an expansion in HTT. However, 15% (20/130) of black South African patients and no white patients (0/171) had an expansion in JPH3, confirming the diagnosis of Huntington disease like 2 (HDL2). Individuals with HDL2 share many clinical features with individuals with HD and are clinically indistinguishable in many cases, although the average age of onset and diagnosis in HDL2 is 5 years later than HD and individual clinical features may be more prominent. HDL2 mutations contribute significantly to the HD phenotype in South Africans with African ancestry. JPH3 haplotype studies in 31 families, mainly from South Africa and North America, provide evidence for a founder mutation and support a common African origin for all HDL2 patients. Molecular testing in individuals with an HD phenotype and African ancestry should include testing routinely for JPH3 mutations. PMID:26079385

  10. Genome-wide association of body fat distribution in African ancestry populations suggests new loci.

    Directory of Open Access Journals (Sweden)

    Ching-Ti Liu

    Full Text Available Central obesity, measured by waist circumference (WC or waist-hip ratio (WHR, is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS of fat distribution among those of predominantly African ancestry (AA. We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1. Overall, 25 SNPs with single genomic control (GC-corrected p-values<5.0 × 10(-6 were followed-up (stage 2 in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24×10(-8 for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48×10(-8 for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5 × 10(-8; RREB1: p = 5.7 × 10(-8. Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN. Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02. In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept

  11. African ancestry and its correlation to type 2 diabetes in African Americans: a genetic admixture analysis in three U.S. population cohorts.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    Full Text Available The risk of type 2 diabetes is approximately 2-fold higher in African Americans than in European Americans even after adjusting for known environmental risk factors, including socioeconomic status (SES, suggesting that genetic factors may explain some of this population difference in disease risk. However, relatively few genetic studies have examined this hypothesis in a large sample of African Americans with and without diabetes. Therefore, we performed an admixture analysis using 2,189 ancestry-informative markers in 7,021 African Americans (2,373 with type 2 diabetes and 4,648 without from the Atherosclerosis Risk in Communities Study, the Jackson Heart Study, and the Multiethnic Cohort to 1 determine the association of type 2 diabetes and its related quantitative traits with African ancestry controlling for measures of SES and 2 identify genetic loci for type 2 diabetes through a genome-wide admixture mapping scan. The median percentage of African ancestry of diabetic participants was slightly greater than that of non-diabetic participants (study-adjusted difference = 1.6%, P<0.001. The odds ratio for diabetes comparing participants in the highest vs. lowest tertile of African ancestry was 1.33 (95% confidence interval 1.13-1.55, after adjustment for age, sex, study, body mass index (BMI, and SES. Admixture scans identified two potential loci for diabetes at 12p13.31 (LOD = 4.0 and 13q14.3 (Z score = 4.5, P = 6.6 × 10(-6. In conclusion, genetic ancestry has a significant association with type 2 diabetes above and beyond its association with non-genetic risk factors for type 2 diabetes in African Americans, but no single gene with a major effect is sufficient to explain a large portion of the observed population difference in risk of diabetes. There undoubtedly is a complex interplay among specific genetic loci and non-genetic factors, which may both be associated with overall admixture, leading to the observed ethnic differences in diabetes

  12. Genome-wide ancestry of 17th-century enslaved Africans from the Caribbean

    DEFF Research Database (Denmark)

    Schroeder, Hannes; Avila-Arcos, Maria C.; Malaspinas, Anna-Sapfo;

    2015-01-01

    enslaved Africans whose remains were recovered on the Caribbean island of Saint Martin. We trace their origins to distinct subcontinental source populations within Africa, including Bantu-speaking groups from northern Cameroon and non-Bantu speakers living in present-day Nigeria and Ghana. To our knowledge...

  13. Association of Circulating Renin and Aldosterone With Osteocalcin and Bone Mineral Density in African Ancestry Families.

    Science.gov (United States)

    Kuipers, Allison L; Kammerer, Candace M; Pratt, J Howard; Bunker, Clareann H; Wheeler, Victor W; Patrick, Alan L; Zmuda, Joseph M

    2016-05-01

    Hypertension is associated with accelerated bone loss, and the renin-angiotensin-aldosterone system is a key regulator of blood pressure. Although components of this system are expressed in human bone cells, studies in humans are sparse. Thus, we studied the association of circulating renin and aldosterone with osteocalcin and bone mineral density. We recruited 373 African ancestry family members without regard to health status from 6 probands (mean family size: 62 and relative pairs: 1687). Participants underwent a clinical examination, dual-energy x-ray absorptiometry, and quantitative computed tomographic scans. Renin activity, aldosterone concentration, and osteocalcin were measured in fasting blood samples. Aldosterone/renin ratio was calculated as aldosterone concentration/renin activity. All models were analyzed using pedigree-based variance components methods. Full models included adjustment for age, sex, body composition, comorbidities, lifestyle factors, blood pressure, and antihypertensive medication. Higher renin activity was significantly associated with lower total osteocalcin and with higher trabecular bone mineral density (bothP<0.01). There were also significant genetic correlations between renin activity and whole-body bone mineral density. There were no associations with aldosterone concentration in any model and results for aldosterone/renin ratio were similar to those for renin activity. This is the first study to report a significant association between renin activity and a marker of bone turnover and bone mineral density in generally healthy individuals. Also, there is evidence for significant genetic pleiotropy and, thus, there may be a shared biological mechanism underlying both the renin-angiotensin-aldosterone system and bone metabolism that is independent of hypertension. PMID:26975710

  14. Association between Plasma 25-Hydroxyvitamin D, Ancestry and Aggressive Prostate Cancer among African Americans and European Americans in PCaP

    Science.gov (United States)

    Steck, Susan E.; Arab, Lenore; Zhang, Hongmei; Bensen, Jeannette T.; Fontham, Elizabeth T. H.; Johnson, Candace S.; Mohler, James L.; Smith, Gary J.; Su, Joseph L.; Trump, Donald L.; Woloszynska-Read, Anna

    2015-01-01

    Background African Americans (AAs) have lower circulating 25-hydroxyvitamin D3 [25(OH)D3] concentrations and higher prostate cancer (CaP) aggressiveness than other racial/ethnic groups. The purpose of the current study was to examine the relationship between plasma 25(OH)D3, African ancestry and CaP aggressiveness among AAs and European Americans (EAs). Methods Plasma 25(OH)D3 was measured using LC-MS/MS (Liquid Chromatography Tandem Mass Spectrometry) in 537 AA and 663 EA newly-diagnosed CaP patients from the North Carolina-Louisiana Prostate Cancer Project (PCaP) classified as having either ‘high’ or ‘low’ aggressive disease based on clinical stage, Gleason grade and prostate specific antigen at diagnosis. Mean plasma 25(OH)D3 concentrations were compared by proportion of African ancestry. Logistic regression was used to calculate multivariable adjusted odds ratios (OR) and 95% confidence intervals (95%CI) for high aggressive CaP by tertile of plasma 25(OH)D3. Results AAs with highest percent African ancestry (>95%) had the lowest mean plasma 25(OH)D3 concentrations. Overall, plasma 25(OH)D3 was associated positively with aggressiveness among AA men, an association that was modified by calcium intake (ORT3vs.T1: 2.23, 95%CI: 1.26–3.95 among men with low calcium intake, and ORT3vs.T1: 0.19, 95%CI: 0.05–0.70 among men with high calcium intake). Among EAs, the point estimates of the ORs were <1.0 for the upper tertiles with CIs that included the null. Conclusions Among AAs, plasma 25(OH)D3 was associated positively with CaP aggressiveness among men with low calcium intake and inversely among men with high calcium intake. The clinical significance of circulating concentrations of 25(OH)D3 and interactions with calcium intake in the AA population warrants further study. PMID:25919866

  15. Body fatness and breast cancer risk in women of African ancestry

    International Nuclear Information System (INIS)

    Obesity has been shown to be inversely associated with breast cancer risk in premenopausal women, while increasing risk in postmenopausal women. However, the current evidence is largely based on studies in Caucasian populations. Associations in women of African ancestry (AA), who have a higher prevalence of obesity, have been evaluated in few studies and results suggest different effects. We evaluated the impact of body size, body fat distribution, and body composition on breast cancer risk among AA women (978 cases and 958 controls) participating in the Women’s Circle of Health Study, a multi-site case–control study in New York City (NYC) and New Jersey (NJ). Cases were newly diagnosed with histologically confirmed ductal carcinoma in situ or invasive breast cancer, age 20–75 yrs. In NYC, cases were recruited through hospitals with the largest referral patterns for AA women and controls through random digit dialing (RDD). In NJ, cases were identified in seven counties in NJ thorough the NJ State Cancer Registry, and controls through RDD and community-based recruitment. During in-person interviews, questionnaires were administered and detailed anthropometric measurements were obtained. Body composition was assessed by bioelectrical impedance analysis. BMI did not have a major impact on pre- or post-menopausal breast cancer, but was significantly associated with reduced risk of ER-/PR- tumors among postmenopausal women (OR: 0.37; 95% CI: 0.15-0.96 for BMI > 30 vs. BMI < 25). Furthermore, increased premenopausal breast cancer risk was found for higher waist and hip circumferences after adjusting for BMI, with ORs of 2.25 (95% CI: 1.07-4.74) and 2.91 (95% CI: 1.39-6.10), respectively, comparing the highest vs. lowest quartile. While ORs for higher fat mass and percent body fat among postmenopausal women were above one, confidence intervals included the null value. Our study suggests that in AA women BMI is generally unrelated to breast cancer. However, higher

  16. The multiethnic ancestry of Bolivians as revealed by the analysis of Y-chromosome markers.

    Science.gov (United States)

    Cárdenas, Jorge Mario; Heinz, Tanja; Pardo-Seco, Jacobo; Álvarez-Iglesias, Vanesa; Taboada-Echalar, Patricia; Sánchez-Diz, Paula; Carracedo, Ángel; Salas, Antonio

    2015-01-01

    We have analyzed the specific male genetic component of 226 Bolivians recruited in five different regions ("departments"), La Paz, Cochabamba, Pando, Beni, and Santa Cruz. To evaluate the effect of geography on the distribution of genetic variability, the samples were also grouped into three main eco-geographical regions, namely, Andean, Sub-Andean, and Llanos. All the individuals were genotyped for 17 Y-STR and 32 Y-SNP markers. The average Y-chromosome Native American component in Bolivians is 28%, and it is mainly represented by haplogroup Q1a3a, while the average Y-chromosome European ancestry is 65%, and it is mainly represented by haplogroup R1b1-P25. The data indicate that there exists significant population sub-division in the country in terms of continental ancestry. Thus, the partition of ancestries in Llanos, Sub-Andean, and Andean regions is as follows (respectively): (i) Native American ancestry: 47%, 7%, and 19%, (ii) European ancestry: 46%, 86%, and 75%, and (iii) African ancestry: 7%, 7%, and 6%. The population sub-structure in the country is also well mirrored when inferred from an AMOVA analysis, indicating that among-population variance in the country reaches 9.74-11.15%. This suggests the convenience of using regional datasets for forensic applications in Bolivia, instead of using a global and single country database. By comparing the Y-chromosome patterns with those previously reported on the same individuals on autosomal SNPs and mitochondrial DNA (mtDNA), it becomes clear that Bolivians show a strong gender-bias. PMID:25450796

  17. African-American mitochondrial DNAs often match mtDNAs found in multiple African ethnic groups

    Directory of Open Access Journals (Sweden)

    Jackson Fatimah

    2006-10-01

    Full Text Available Abstract Background Mitochondrial DNA (mtDNA haplotypes have become popular tools for tracing maternal ancestry, and several companies offer this service to the general public. Numerous studies have demonstrated that human mtDNA haplotypes can be used with confidence to identify the continent where the haplotype originated. Ideally, mtDNA haplotypes could also be used to identify a particular country or ethnic group from which the maternal ancestor emanated. However, the geographic distribution of mtDNA haplotypes is greatly influenced by the movement of both individuals and population groups. Consequently, common mtDNA haplotypes are shared among multiple ethnic groups. We have studied the distribution of mtDNA haplotypes among West African ethnic groups to determine how often mtDNA haplotypes can be used to reconnect Americans of African descent to a country or ethnic group of a maternal African ancestor. The nucleotide sequence of the mtDNA hypervariable segment I (HVS-I usually provides sufficient information to assign a particular mtDNA to the proper haplogroup, and it contains most of the variation that is available to distinguish a particular mtDNA haplotype from closely related haplotypes. In this study, samples of general African-American and specific Gullah/Geechee HVS-I haplotypes were compared with two databases of HVS-I haplotypes from sub-Saharan Africa, and the incidence of perfect matches recorded for each sample. Results When two independent African-American samples were analyzed, more than half of the sampled HVS-I mtDNA haplotypes exactly matched common haplotypes that were shared among multiple African ethnic groups. Another 40% did not match any sequence in the database, and fewer than 10% were an exact match to a sequence from a single African ethnic group. Differences in the regional distribution of haplotypes were observed in the African database, and the African-American haplotypes were more likely to match haplotypes

  18. Determining the effects and challenges of incorporating genetic testing into primary care management of hypertensive patients with African ancestry.

    Science.gov (United States)

    Horowitz, C R; Abul-Husn, N S; Ellis, S; Ramos, M A; Negron, R; Suprun, M; Zinberg, R E; Sabin, T; Hauser, D; Calman, N; Bagiella, E; Bottinger, E P

    2016-03-01

    People of African ancestry (Blacks) have increased risk of kidney failure due to numerous socioeconomic, environmental, and clinical factors. Two variants in the APOL1 gene are now thought to account for much of the racial disparity associated with hypertensive kidney failure in Blacks. However, this knowledge has not been translated into clinical care to help improve patient outcomes and address disparities. GUARDD is a randomized trial to evaluate the effects and challenges of incorporating genetic risk information into primary care. Hypertensive, non-diabetic, adults with self-reported African ancestry, without kidney dysfunction, are recruited from diverse clinical settings and randomized to undergo APOL1 genetic testing at baseline (intervention) or at one year (waitlist control). Providers are educated about genomics and APOL1. Guided by a genetic counselor, trained staff return APOL1 results to patients and provide low-literacy educational materials. Real-time clinical decision support tools alert clinicians of their patients' APOL1 results and associated risk status at the point of care. Our academic-community-clinical partnership designed a study to generate information about the impact of genetic risk information on patient care (blood pressure and renal surveillance) and on patient and provider knowledge, attitudes, beliefs, and behaviors. GUARDD will help establish the effective implementation of APOL1 risk-informed management of hypertensive patients at high risk of CKD, and will provide a robust framework for future endeavors to implement genomic medicine in diverse clinical practices. It will also add to the important dialog about factors that contribute to and may help eliminate racial disparities in kidney disease. PMID:26747051

  19. Comparison of Genome Wide Variation between Malawians and African Ancestry HapMap Populations

    OpenAIRE

    Joubert, Bonnie R.; North, Kari E.; Wang, Yunfei; Mwapasa, Victor; Franceschini, Nora; Meshnick, Steven R; Lange, Ethan M.

    2010-01-01

    Understanding genetic variation between populations is important because it affects the portability of human genome wide analytical methods. We compared genetic variation and substructure between Malawians and other African and non-African HapMap populations. Allele frequencies and adjacent linkage disequilibrium (LD) were measured for 617,715 single nucleotide polymorphisms (SNPs) across subject genomes. Allele frequencies in the Malawian population (N = 226) were highly correlated with alle...

  20. The evolution of skin pigmentation and hair texture in people of African ancestry.

    Science.gov (United States)

    Jablonski, Nina G; Chaplin, George

    2014-04-01

    Our species, Homo sapiens, evolved in Africa, and humanity's highest levels of genetic diversity are maintained there today. Underlying genetic diversity combined with the great range of solar regimes and climatic conditions found in Africa has contributed to a wide range of human integumentary phenotypes within the continent. Millions of Africans have moved, voluntarily and involuntarily, to other continents in the past 2000 years, and the range of integumentary phenotypes among admixed African diaspora populations is enormous. In this contribution, we do not catalog this variation, but provide basic evolutionary background as to how it developed in the first place. PMID:24679998

  1. Habitual Diets Rich in Dark-Green Vegetables Are Associated with an Increased Response to ω-3 Fatty Acid Supplementation in Americans of African Ancestry123

    OpenAIRE

    O’Sullivan, Aifric; Armstrong, Patrice; Schuster, Gertrud U.; Pedersen, Theresa L.; Allayee, Hooman; Stephensen, Charles B.; Newman, John W.

    2013-01-01

    Although substantial variation exists in individual responses to omega-3 (ω-3) (n–3) fatty acid supplementation, the causes for differences in response are largely unknown. Here we investigated the associations between the efficacy of ω-3 fatty acid supplementation and a broad range of nutritional and clinical factors collected during a double-blind, placebo-controlled trial in participants of African ancestry, randomly assigned to receive either 2 g eicosapentaenoic acid (EPA) + 1 g docosahe...

  2. From continental priorities to local conservation: a multi-level analysis for African tortoises.

    Directory of Open Access Journals (Sweden)

    Pierluigi Bombi

    Full Text Available Terrestrial tortoises are the most endangered group of vertebrates but they are still largely ignored for defining global conservation priorities. In this paper, we explored within a hierarchical framework the potential contribution of prioritization studies at the continental scale to the planning of local initiatives for the conservation of African tortoises at the regional level. First, we modeled the distribution of all the African tortoise species, we calculated three indicators of conservation priority (i.e., species richness, conservation value, and complementarity, and we carried out a gap analysis at continental scale. Second, we focused on the most important region for tortoise conservation and performed the same analyses at higher resolution. Finally, we compared the results from the two scales for understanding the degree to which they are complementary. Southern Africa emerged from the continental analysis as the most important region for tortoises. Within this area, the high-resolution analysis pointed out specific core sites for conservation. The relative degree of species protection was assessed similarly at the two different resolutions. Two species appeared particularly vulnerable at both scales. Priority indices calculated at high resolution were correlated to the values calculated for the corresponding cells at low resolution but the congruence was stronger for species richness. Our results suggest to integrate the calculation of conservation value and complementarity into a hierarchical framework driven by species richness. The advantages of large scale planning include its broad perspective on complementarity and the capability to identify regions with greatest conservation potential. In this light, continental analyses allow targeting fine scale studies toward regions with maximum priority. The regional analyses at fine scale allow planning conservation measure at a resolution similar to that required for the practical

  3. Recurrent BRCA1 and BRCA2 mutations in breast cancer patients of African ancestry.

    Science.gov (United States)

    Zhang, Jing; Fackenthal, James D; Zheng, Yonglan; Huo, Dezheng; Hou, Ningqi; Niu, Qun; Zvosec, Cecilia; Ogundiran, Temidayo O; Hennis, Anselm J; Leske, Maria Cristina; Nemesure, Barbara; Wu, Suh-Yuh; Olopade, Olufunmilayo I

    2012-07-01

    Recurrent mutations constituted nearly three quarters of all BRCA1 mutations and almost half of all BRCA2 mutations identified in the first cohort of the Nigerian Breast Cancer Study. To further characterize breast/ovarian cancer risks associated with BRCA1/BRCA2 mutations in the African diaspora, we genotyped recurrent mutations among Nigerian, African American, and Barbadian breast cancer patients. A replication cohort of 356 Nigerian breast cancer patients was genotyped for 12 recurrent BRCA1/2 mutant alleles (Y101X, 1742insG, 4241delTG, M1775R, 4359insC, C64Y, 1623delTTAAA, Q1090X, and 943ins10 from BRCA1, and 1538delAAGA, 2630del11, and 9045delGAAA from BRCA2) by means of SNaPshot followed by direct sequencing or by direct sequencing alone. In addition, 260 African Americans and 118 Barbadians were genotyped for six of the recurrent BRCA1 mutations by SNaPshot assay. Of all the BRCA1/2 recurrent mutations we identified in the first cohort, six were identified in 11 patients in the replication study. These mutation carriers constitute 3.1 % [95 % Confidence Interval (CI) 1.6-5.5 %] of the replication cohort. By comparison, 6.9 % (95 % CI 4.7-9.7 %) of the discovery cohort carried BRCA1/2 recurrent mutations. For the subset of recurrent mutations we tested in breast cancer cases from Barbados or the United States, only two 943ins10 carriers were identified in African Americans. Nigerian breast cancer patients from Ibadan carry a broad and unique spectrum of BRCA1/2 mutations. Our data suggest that BRCA1/2 mutation testing limited to recurrent mutations is not sufficient to understand the BRCA1/2-associated breast cancer risk in African populations in the diaspora. As the cost of Sanger sequencing is considerably reduced, deploying innovative technologies such as high throughput DNA sequencing of BRCA1/2 and other cancer susceptibility genes will be essential for identifying high-risk individuals and families to reduce the burden of aggressive early onset breast

  4. Habitual diets rich in dark-green vegetables are associated with an increased response to ω-3 fatty acid supplementation in Americans of African ancestry.

    Science.gov (United States)

    O'Sullivan, Aifric; Armstrong, Patrice; Schuster, Gertrud U; Pedersen, Theresa L; Allayee, Hooman; Stephensen, Charles B; Newman, John W

    2014-02-01

    Although substantial variation exists in individual responses to omega-3 (ω-3) (n-3) fatty acid supplementation, the causes for differences in response are largely unknown. Here we investigated the associations between the efficacy of ω-3 fatty acid supplementation and a broad range of nutritional and clinical factors collected during a double-blind, placebo-controlled trial in participants of African ancestry, randomly assigned to receive either 2 g eicosapentaenoic acid (EPA) + 1 g docosahexaenoic acid (n = 41) or corn/soybean oil placebo (n = 42) supplements for 6 wk. Food-frequency questionnaires were administered, and changes in erythrocyte lipids, lipoproteins, and monocyte 5-lipoxygenase-dependent metabolism were measured before and after supplementation. Mixed-mode linear regression modeling identified high (n = 28) and low (n = 13) ω-3 fatty acid response groups on the basis of changes in erythrocyte EPA abundance (P orange vegetables and legumes (P = 0.01) and a lower intake of vegetables (P = 0.02), particularly dark-green vegetables (P = 0.002). Because the findings reported here are associative in nature, prospective studies are needed to determine if dietary dark-green vegetables or nutrients contained in these foods can enhance the efficacy of ω-3 fatty acid supplements. This trial was registered at clinicaltrials.gov as NCT00536185. PMID:24259553

  5. Effects of interleukin-10 on cutaneous wounds and scars in humans of African continental ancestral origin.

    Science.gov (United States)

    Kieran, Ingrid; Taylor, Catherine; Bush, Jim; Rance, Mark; So, Karen; Boanas, Adam; Metcalfe, Anthony; Hobson, Rosalind; Goldspink, Nick; Hutchison, John; Ferguson, Mark

    2014-01-01

    Scars in humans of African continental ancestry heal with an exaggerated inflammatory response and a generally wider scar. Interleukin-10 is an anti-inflammatory and antifibrotic cytokine. A randomized controlled trial in Caucasians found that exogenous interleukin-10 resulted in improved macroscopic scar appearance and reduced scar redness. We investigated the effects of interleukin-10 on cutaneous scarring in volunteers of African ancestral origin in an exploratory, single-center, within-subject, double-blind randomized controlled trial. Fifty-six subjects received two of four potential prerandomized concentrations of interleukin-10 (5, 25, 100, and 250 ng/100 µL) in two full-thickness incisions on the upper inner arms. Anatomically matching incisions on the contralateral arm were treated with placebo. Scars were excised at 1 month for histological analysis and were redosed with the same regimen. Resultant excision scars were followed up for 12 months for scar width measurement and scoring. Scoring was performed by trial doctors, subjects, and a panel. Incisions treated with 100 ng/100 µL interleukin-10 had significantly reduced microscopic scar widths. Incisions treated with 5 and 25 ng/100 µL interleukin-10 were also narrower, but not significantly. There were no differences observed in pro-inflammatory or pro-fibrotic markers between interleukin-10 and placebo treatment. There was no long-term evidence that 100 ng/100 µL interleukin-10 had a therapeutic effect on macroscopic scar width or appearance, as excisions treated with this concentration were significantly wider than placebo between 8 and 12 months of maturation. Doctors showed a trend toward favoring the macroscopic appearance of placebo-treated excisions compared with those treated with 250 ng/100 µL interleukin-10. Panelists scored placebo-treated excisions as significantly better-appearing than those treated with 250 ng/100 µL interleukin-10. Doctors' scores showed a

  6. Association of the BANK1 R61H variant with systemic lupus erythematosus in Americans of European and African ancestry

    Directory of Open Access Journals (Sweden)

    Struan FA Grant

    2008-12-01

    Full Text Available Struan FA Grant1,2,3, Michelle Petri4, Jonathan P Bradfield1, Cecilia E Kim1, Erin Santa1, Kiran Annaiah1, Edward C Frackelton1, Joseph T Glessner1, F George Otieno1, Julie L Shaner1, Ryan M Smith1, Andrew W Eckert1, Rosetta M Chiavacci1, Marcin Imielinski1, Kathleen E Sullivan5, Hakon Hakonarson1,2,31Center for Applied Genomics, Abramson Research Center, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA; 2Department of Pediatrics and Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA; 3Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA; 4Division of Rheumatology, Johns Hopkins School of Medicine, Baltimore, MD, USA; 5Division of Allergy and Immunology, Abramson Research Center, The Children’s Hospital of Philadelphia, Philadelphia, PA, USAAbstract: Recently an association was demonstrated between the single nucleotide polymorphism (SNP, rs10516487, within the B-cell gene BANK1 and systemic lupus erythematosus (SLE as a consequence of a genome wide association study of this disease in European and Argentinean populations. In a bid for replication, we examined the effects of the R61H non-synonymous variant with respect to SLE in our genotyped American cohorts of European and African ancestry. Utilizing data from our ongoing genome-wide association study in our cohort of 178 Caucasian SLE cases and 1808 Caucasian population-based controls plus 148 African American (AA SLE cases and 1894 AA population-based controls we investigated the association of the previously described non-synonymous SNP at the BANK1 locus with the disease in the two ethnicities separately. Using a Fisher’s exact test, the minor allele frequency (MAF of rs10516487 in the Caucasian cases was 22.6% while it was 31.2% in Caucasian controls, yielding a protective odds ratio (OR of 0.64 (95% CI 0.49–0.85; one-sided p = 7.07 × 10−4. Furthermore, the MAF of rs10516487 in the

  7. The Agulhas-Karoo Geoscience Transect: Structures and processes along the southern African continental margin

    OpenAIRE

    N. Parsiegla; Gohl, K.; G. Uenzelmann-Neben; Jacek Stankiewicz

    2008-01-01

    The southern African continental transform margin is of great interest for the understanding of processes related to continental breakup, transform fault formation and vertical plate motion. Open questions include the cause and consequences for the high topography of southern Africa, neotectonic activity along the Agulhas-Falkland Fracture Zone and the formation of the Outeniqua Basin. As a component of the project “Inkaby yeAfrica”, the 900 km long Agulhas-Karoo Geoscience Transect was carri...

  8. Development of a panel of genome-wide ancestry informative markers to study admixture throughout the Americas.

    Directory of Open Access Journals (Sweden)

    Joshua Mark Galanter

    Full Text Available Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R² > 0.9 for ancestral components with significant between-subject variance. Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.

  9. Development of a Panel of Genome-Wide Ancestry Informative Markers to Study Admixture Throughout the Americas

    Science.gov (United States)

    Galanter, Joshua Mark; Fernandez-Lopez, Juan Carlos; Gignoux, Christopher R.; Barnholtz-Sloan, Jill; Fernandez-Rozadilla, Ceres; Via, Marc; Hidalgo-Miranda, Alfredo; Contreras, Alejandra V.; Figueroa, Laura Uribe; Raska, Paola; Jimenez-Sanchez, Gerardo; Silva Zolezzi, Irma; Torres, Maria; Ponte, Clara Ruiz; Ruiz, Yarimar; Salas, Antonio; Nguyen, Elizabeth; Eng, Celeste; Borjas, Lisbeth; Zabala, William; Barreto, Guillermo; Rondón González, Fernando; Ibarra, Adriana; Taboada, Patricia; Porras, Liliana; Moreno, Fabián; Bigham, Abigail; Gutierrez, Gerardo; Brutsaert, Tom; León-Velarde, Fabiola; Moore, Lorna G.; Vargas, Enrique; Cruz, Miguel; Escobedo, Jorge; Rodriguez-Santana, José; Rodriguez-Cintrón, William; Chapela, Rocio; Ford, Jean G.; Bustamante, Carlos; Seminara, Daniela; Shriver, Mark; Ziv, Elad; Gonzalez Burchard, Esteban; Haile, Robert

    2012-01-01

    Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R2>0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region. PMID:22412386

  10. Genetic structure in four West African population groups

    Directory of Open Access Journals (Sweden)

    Chen Guanjie

    2005-06-01

    Full Text Available Abstract Background Africa contains the most genetically divergent group of continental populations and several studies have reported that African populations show a high degree of population stratification. In this regard, it is important to investigate the potential for population genetic structure or stratification in genetic epidemiology studies involving multiple African populations. The presences of genetic sub-structure, if not properly accounted for, have been reported to lead to spurious association between a putative risk allele and a disease. Within the context of the Africa America Diabetes Mellitus (AADM Study (a genetic epidemiologic study of type 2 diabetes mellitus in West Africa, we have investigated population structure or stratification in four ethnic groups in two countries (Akan and Gaa-Adangbe from Ghana, Yoruba and Igbo from Nigeria using data from 372 autosomal microsatellite loci typed in 493 unrelated persons (986 chromosomes. Results There was no significant population genetic structure in the overall sample. The smallest probability is associated with an inferred cluster of 1 and little of the posterior probability is associated with a higher number of inferred clusters. The distribution of members of the sample to inferred clusters is consistent with this finding; roughly the same proportion of individuals from each group is assigned to each cluster with little variation between the ethnic groups. Analysis of molecular variance (AMOVA showed that the between-population component of genetic variance is less than 0.1% in contrast to 99.91% for the within population component. Pair-wise genetic distances between the four ethnic groups were also very similar. Nonetheless, the small between-population genetic variance was sufficient to distinguish the two Ghanaian groups from the two Nigerian groups. Conclusion There was little evidence for significant population substructure in the four major West African ethnic groups

  11. Southern African continental margin: Dynamic processes of a transform margin

    OpenAIRE

    N. Parsiegla; Jacek Stankiewicz; Gohl, K.; Trond Ryberg; G. Uenzelmann-Neben;  

    2009-01-01

    Dynamic processes at sheared margins associated with the formation of sedimentary basins and marginal ridges are poorly understood. The southern African margin provides an excellent opportunity to investigate the deep crustal structure of a transform margin and to characterize processes acting at these margins by studying the Agulhas-Falkland Fracture Zone, the Outeniqua Basin, and the Diaz Marginal Ridge. To do this, we present the results of the combined seismic land-sea experiments of the ...

  12. Identification, replication, and fine-mapping of Loci associated with adult height in individuals of african ancestry.

    OpenAIRE

    Amidou N'Diaye; Chen, Gary K.; Palmer, Cameron D; Bing Ge; Bamidele Tayo; Rasika A Mathias; Jingzhong Ding; Michael A Nalls; Adebowale Adeyemo; Véronique Adoue; Ambrosone, Christine B.; Larry Atwood; Bandera, Elisa V.; Becker, Lewis C.; Berndt, Sonja I.

    2011-01-01

    Adult height is a classic polygenic trait of high heritability (h(2) approximately 0.8). More than 180 single nucleotide polymorphisms (SNPs), identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain approximately10% of the variance in height. Discovery efforts in other populations, while limited, have revealed loci for height not previously implicated in individuals of European ancestry. Here, we performed a meta-analy...

  13. Identification, Replication, and Fine-Mapping of Loci Associated with Adult Height in Individuals of African Ancestry

    OpenAIRE

    N'Diaye, Amidou; Chen, Gary K.; Palmer, Cameron D; Ge, Bing; Tayo, Bamidele; Rasika A Mathias; Ding, Jingzhong; Michael A Nalls; Adeyemo, Adebowale; Adoue, Véronique; Ambrosone, Christine B.; Atwood, Larry; Bandera, Elisa V.; Becker, Lewis C.; Berndt, Sonja I.

    2011-01-01

    Author Summary Adult height is an ideal phenotype to improve our understanding of the genetic architecture of complex diseases and traits: it is easily measured and usually available in large cohorts, relatively stable, and mostly influenced by genetics (narrow-sense heritability of height h 2∼0.8). Genome-wide association (GWA) studies in individuals of European ancestry have identified >180 single nucleotide polymorphisms (SNPs) associated with height. In the current study, we continued to ...

  14. Food Group Categories of Low-Income African American Women

    Science.gov (United States)

    Lynch, Elizabeth B.; Holmes, Shane

    2011-01-01

    Objective: Describe lay food group categories of low-income African American women and assess the overlap of lay food groups and MyPyramid food groups. Design: A convenience sample of African American mothers from a low-income Chicago neighborhood performed a card-sorting task in which they grouped familiar food items into food groups. Setting:…

  15. Genomic study of the Ket: a Paleo-Eskimo-related ethnic group with significant ancient North Eurasian ancestry.

    Science.gov (United States)

    Flegontov, Pavel; Changmai, Piya; Zidkova, Anastassiya; Logacheva, Maria D; Altınışık, N Ezgi; Flegontova, Olga; Gelfand, Mikhail S; Gerasimov, Evgeny S; Khrameeva, Ekaterina E; Konovalova, Olga P; Neretina, Tatiana; Nikolsky, Yuri V; Starostin, George; Stepanova, Vita V; Travinsky, Igor V; Tříska, Martin; Tříska, Petr; Tatarinova, Tatiana V

    2016-01-01

    The Kets, an ethnic group in the Yenisei River basin, Russia, are considered the last nomadic hunter-gatherers of Siberia, and Ket language has no transparent affiliation with any language family. We investigated connections between the Kets and Siberian and North American populations, with emphasis on the Mal'ta and Paleo-Eskimo ancient genomes, using original data from 46 unrelated samples of Kets and 42 samples of their neighboring ethnic groups (Uralic-speaking Nganasans, Enets, and Selkups). We genotyped over 130,000 autosomal SNPs, identified mitochondrial and Y-chromosomal haplogroups, and performed high-coverage genome sequencing of two Ket individuals. We established that Nganasans, Kets, Selkups, and Yukaghirs form a cluster of populations most closely related to Paleo-Eskimos in Siberia (not considering indigenous populations of Chukotka and Kamchatka). Kets are closely related to modern Selkups and to some Bronze and Iron Age populations of the Altai region, with all these groups sharing a high degree of Mal'ta ancestry. Implications of these findings for the linguistic hypothesis uniting Ket and Na-Dene languages into a language macrofamily are discussed. PMID:26865217

  16. The development of continental crust through geological time: the South African case

    International Nuclear Information System (INIS)

    Nd isotopic compositions and 147Sm/144Nd ratios were measured in fifty-eight South African shales and greywackes with depositional ages ranging from 0.2 to 3.3 b.y. Elements such as the rare earths, which are poorly soluble in water and not fractionated during exogeneous processes, preserve the signature of the original crustal source. The 147Sm/144Nd ratios appear to be approximately constant throughout the time interval sampled. We calculated Nd model ages of crustal differentiation. Knowing that the shales represent a true blend of different continental areas we consider these model ages representative of the mean ages of their primitive continental sources. Then, using the inverse technique developed by Allegre and Rousseau in 1984, we computed a growth curve for the continental crust in South Africa. Two periods of important crustal genesis (Archaean and around 1.5 b.y.) can be compared with the observed geology and with other continental crust growth curves obtained in previous studies in southern Africa and in Australia. The observation of large variations in the MgO content and Ni, Cr, U and Th concentrations between Archaean South African shales and post-Archaean samples compared to the constancy of the 147Sm/144Nd ratios leads us to propose that the Archaean crust was composed of both granite (70.5%) and a mafic component (29.5%) which could have been komatiite. The small dispersion of 147Sm/144Nd ratios suggests that erosion and sedimentation processes yielded homogeneous Archaean shales. The present-day continental crust is much more heterogeneous, because it has undergone several episodes of recycling. Thus recent shales are characterized by more variable 147Sm/144Nd ratios. (orig.)

  17. Counseling Groups for African American Women: A Focus on Spirituality.

    Science.gov (United States)

    Williams, Carmen Braun; Frame, Marsha Wiggins; Green, Evelyn

    1999-01-01

    Explains cultural and spiritual traditions within African American women's experience that form the foundation for group counseling strategies. Reviews literature regarding African American women's experience in groups. Explains group interventions such as art, music, dance, imagery, journaling, and rituals that can help transcend, empower, and…

  18. ADH1B is associated with alcohol dependence and alcohol consumption in populations of European and African ancestry

    OpenAIRE

    Bierut, Laura Jean; Goate, Alison M.; Breslau, Naomi; Johnson, Eric O.; Bertelsen, Sarah; Fox, Louis; Agrawal, Arpana; Bucholz, Kathleen K.; Grucza, Richard; Hesselbrock, Victor; Kramer, John; Kuperman, Samuel; Nurnberger, John; Porjesz, Bernice; Saccone, Nancy L.

    2011-01-01

    A coding variant in ADH1B (rs1229984) that leads to the replacement of Arg48 with His48 is common in Asian populations and reduces their risk for alcoholism, but because of very low allele frequencies the effects in European or African populations have been difficult to detect. We genotyped and analyzed this variant in three large European and African-American case-control studies in which alcohol dependence was defined by DSM-IV criteria, and demonstrated a strong protective effect of the Hi...

  19. Multiproxy characterization and budgeting of terrigenous end-members at the NW African continental margin

    OpenAIRE

    Just, J; D. Heslop; Dobeneck, T. von; Bickert, T.; Dekkers, M.J.; Frederichs, T.; Meyer, I.; Zabel, M.

    2012-01-01

    Grain-size, terrigenous element and rock magnetic remanence data of Quaternary marine sediments retrieved at the NW African continental margin off Gambia (gravity core GeoB 13602–1, 13°32.71′N, 17°50.96′W) were jointly analyzed by end-member (EM) unmixing methods to distinguish and budget past terrigenous fluxes. We compare and cross-validate the identified single-parameter EM systems and develop a numerical strategy to calculate associated multiparameter EM properties. One aeolian and two fl...

  20. Indices of Paraoxonase and Oxidative Status Do Not Enhance the Prediction of Subclinical Cardiovascular Disease in Mixed-Ancestry South Africans

    Directory of Open Access Journals (Sweden)

    M. Macharia

    2014-01-01

    Full Text Available We evaluated the association of indices of paraoxonase (PON1 and oxidative status with subclinical cardiovascular disease (CVD in mixed-ancestry South Africans. Participants were 491 adults (126 men who were stratified by diabetes status and body mass index (BMI. Carotid intima-media thickness (CIMT was used as a measure of subclinical CVD. Indices of PON1 and oxidative status were determined by measuring levels and activities (paraoxonase and arylesterase of PON1, antioxidant activity (ferric reducing antioxidant power and trolox equivalent antioxidant capacity, and lipid peroxidation markers (malondialdehyde and oxidized LDL. Diabetic subjects (28.9% displayed a significant decrease in PON1 status and antioxidant activity as well as increase in oxidized LDL and malondialdehyde. A similar profile was apparent across increasing BMI categories. CIMT was higher in diabetic than nondiabetic subjects (P<0.0001  but showed no variation across BMI categories. Overall, CIMT correlated negatively with indices of antioxidant activity and positively with measures of lipid oxidation. Sex, age, BMI, and diabetes altogether explained 29.2% of CIMT, with no further improvement from adding PON1 and/or antioxidant status indices. Though indices of PON1 and oxidative status correlate with CIMT, their measurements may not be useful for identifying subjects at high CVD risk in this population.

  1. A panel of 74 AISNPs: Improved ancestry inference within Eastern Asia.

    Science.gov (United States)

    Li, Cai-Xia; Pakstis, Andrew J; Jiang, Li; Wei, Yi-Liang; Sun, Qi-Fan; Wu, Hong; Bulbul, Ozlem; Wang, Ping; Kang, Long-Li; Kidd, Judith R; Kidd, Kenneth K

    2016-07-01

    Many ancestry informative SNP (AISNP) panels have been published. Ancestry resolution in them varies from three to eight continental clusters of populations depending on the panel used. However, none of these panels differentiates well among East Asian populations. To meet this need, we have developed a 74 AISNP panel after analyzing a much larger number of SNPs for Fst and allele frequency differences between two geographically close population groups within East Asia. The 74 AISNP panel can now distinguish at least 10 biogeographic groups of populations globally: Sub-Saharan Africa, North Africa, Europe, Southwest Asia, South Asia, North Asia, East Asia, Southeast Asia, Pacific and Americas. Compared with our previous 55-AISNP panel, Southeast Asia and North Asia are two newly assignable clusters. For individual ancestry assignment, the likelihood ratio and ancestry components were analyzed on a different set of 500 test individuals from 11 populations. All individuals from five of the test populations - Yoruba (YRI), European (CEU), Han Chinese in Henan (CHNH), Rondonian Surui (SUR) and Ticuna (TIC) - were assigned to their appropriate geographical regions unambiguously. For the other test populations, most of the individuals were assigned to their self-identified geographical regions with a certain degree of overlap with adjacent populations. These alternative ancestry components for each individual thus help give a clearer picture of the possible group origins of the individual. We have demonstrated that the new AISNP panel can achieve a deeper resolution of global ancestry. PMID:27077960

  2. Local Ancestry Inference in a Large US-Based Hispanic/Latino Study: Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

    Science.gov (United States)

    Browning, Sharon R; Grinde, Kelsey; Plantinga, Anna; Gogarten, Stephanie M; Stilp, Adrienne M; Kaplan, Robert C; Avilés-Santa, M Larissa; Browning, Brian L; Laurie, Cathy C

    2016-01-01

    We estimated local ancestry on the autosomes and X chromosome in a large US-based study of 12,793 Hispanic/Latino individuals using the RFMix method, and we compared different reference panels and approaches to local ancestry estimation on the X chromosome by means of Mendelian inconsistency rates as a proxy for accuracy. We developed a novel and straightforward approach to performing ancestry-specific PCA after finding artifactual behavior in the results from an existing approach. Using the ancestry-specific PCA, we found significant population structure within African, European, and Amerindian ancestries in the Hispanic/Latino individuals in our study. In the African ancestral component of the admixed individuals, individuals whose grandparents were from Central America clustered separately from individuals whose grandparents were from the Caribbean, and also from reference Yoruba and Mandenka West African individuals. In the European component, individuals whose grandparents were from Puerto Rico diverged partially from other background groups. In the Amerindian ancestral component, individuals clustered into multiple different groups depending on the grandparental country of origin. Therefore, local ancestry estimation provides further insight into the complex genetic structure of US Hispanic/Latino populations, which must be properly accounted for in genotype-phenotype association studies. It also provides a basis for admixture mapping and ancestry-specific allele frequency estimation, which are useful in the identification of risk factors for disease. PMID:27172203

  3. Shallow-mantle Recycling and Anomalous, Voluminous Volcanism along the Northern and Northwestern African Continental Margin

    Science.gov (United States)

    Bryce, J. G.; Blichert-Toft, J.; Graham, D. W.; Miller, S. A.

    2015-12-01

    Mantle-derived volcanism on Earth's surface is generally associated with magma generation as a consequence of volatile addition to suprasubduction zone mantle or in response to decompression melting at diverging plates or in thermochemical anomalies thought to originate deep in the convecting mantle. Many of the hotspots surrounding the northern and northwestern African margin are thought to originate from decompression melting due to upwellings from deep thermochemical anomalies. Similar compositions of lavas erupted in Sicily in the Hyblean Plateau and Mount Etna, Europe's largest most active volcano, have been attributed to contributions from subduction zone enrichments. Considering high-MgO lavas from the northern to northwestern African-Mediterranean margins in the context of recent petrologic models we find the strong majority of the lavas in this region are predominantly alkaline and bear geochemical signatures consistent with derivation from fusible lithologies (volatilized peridotite and/or pyroxenite) [1]. Such results are consistent with implications from recent experimental results that suggest that the mobilization of hydrous, carbonate-rich melts commonly occurs during subduction zone processing [2]. Accordingly, we argue many products generally considered "hot spot" volcanism in this region largely result from partial melting of easily fusible pyroxene-rich and carbonated mantle domains that are relics of shallow-level recycling of volatile-rich melts and/or lithosphere shed during plate boundary processes along the African margin. Long-lived volcanism near continental margins subsequently develops as a consequence of convective anomalies associated with unique tectonic arrangements (oversteepened slabs or slab windows) [3] or, alternatively, as manifestations of convective tectonic anomalies beneath thin lithosphere juxtaposed next to thicker, more stable continental margins [4]. [1] Herzberg and Asimow, 2008; [2] Poli, 2015; [3] Schellart, 2010; [4

  4. Both serum 25-hydroxyvitamin D and calcium levels may increase the risk of incident prostate cancer in Caribbean men of African ancestry.

    Science.gov (United States)

    Jackson, Maria D; Tulloch-Reid, Marshall K; Lindsay, Carole M; Smith, Garrett; Bennett, Franklyn I; McFarlane-Anderson, Norma; Aiken, William; Coard, Kathleen C M

    2015-06-01

    Circulating 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with both higher and lower risk of prostate cancer (PCa), whereas elevated levels of circulating calcium has been related to higher risks. However, there are few studies that account for effects of both calcium and 25(OH)D concentrations on incident PCa in a black population. We examined these relationships in a case-control study of men 40-80 years old with newly diagnosed, histologically confirmed PCa in Jamaica, a tropical country. Mean serum calcium concentrations was higher among cases (2.32 ± 0.19 mmol/L) than controls, (2.27 ± 0.30 mmol/L) (P = 0.023) however, there were no differences in 25(OH)D by cancer status (cases, 33.67 ± 12.71 ng/mL; controls (32.25 ± 12.59 ng/mL). Serum calcium was not correlated with 25(OH)D (partial correlation: r, 0.06; P = 0.287). Multivariable-adjusted models showed a positive linear relationship between PCa and serum calcium (OR, 1.12; CI, 1.00-1.25 per 0.1 nmol/L). Serum 25(OH)D concentration also showed a positive association with PCa (OR, 1.23; CI, 1.01-1.49 per 10 ng/mL). The odds of PCa in men with serum 25(OH)D tertile 2 was OR, 2.18; CI, 1.04-4.43 and OR, 2.47 CI, 1.20-4.90 for tertile 3 (P(trend) = 0.013). Dietary intakes of calcium showed no relationship with PCa. Despite the strong relationship between serum calcium and vitamin D the mechanism by which each affects prostate cancer risk in men of African ancestry needs additional investigation. PMID:25858172

  5. Reconstruction of Holocene southern African continental climate using biomarkers from salt pan sediments

    Science.gov (United States)

    Belz, Lukas; Schüller, Irka; Wehrmann, Achim; Wilkes, Heinz

    2015-04-01

    The climate system of southern Africa is strongly influenced by large scale atmospheric and marine circulation processes and, therefore, very sensitive to global climate change. Recent publications provided evidence for strong spatial and temporal climate variability in southern Africa over the Holocene. It is of major importance to understand the mechanisms driving the southern African climate system in order to estimate regional implications of current global change. However, proxy datasets from continental geoarchives especially of the semi-arid western Kalahari region are still scarce. A main problem is the absence of conventional continental climatic archives, due to the lack of lacustrine systems. In this study we are exploring the utility of sediments from western Kalahari salt pans, i.e. local depressions which are flooded temporarily during rainfall events. Besides the analyses of basic geochemical bulk parameters including TOC, δ13Corg, TIC, δ13Ccarb, δ18Ocarb, TN, δ15N, the paleo-climatic approach focuses on reconstruction of local vegetation assemblages to identify changes in the ecosystem. This is pursued using plant biomarkers, particularly leaf wax n-alkanes and n-alcohols and their stable carbon and hydrogen isotopic signatures. Preliminary results show prominent shifts in n-alkane distribution and δ13C values of the C33 homologue during late Pleistocene and early Holocene. These shifts correlate to changes of the TOC content. Our data indicate changes in carbon sources which possibly reflect major environmental changes.

  6. No association between genetic ancestry and susceptibility to asthma or atopy in Canary Islanders.

    Science.gov (United States)

    Pino-Yanes, María; Corrales, Almudena; Cumplido, José; González, Ruperto; Torres-Galván, María José; Fernández, Orlando Acosta; Sánchez-Machín, Inmaculada; Figueroa, Javier; Sánchez-Palacios, Anselmo; Villar, Jesús; Hernández, Mariano; Carrillo, Teresa; Flores, Carlos

    2012-09-01

    Asthma is a complex respiratory disease characterized by chronic inflammation of airways and frequently associated with atopic symptoms. The population from the Canary Islands, which has resulted from a recent admixture of North African and Iberian populations, shows the highest prevalence of asthma and atopic symptoms among the Spanish populations. Although environmental particularities would account for the majority of such disparity, genetic ancestry might play a role in increasing the susceptibility of asthma or atopy, as have been demonstrated in other recently African-admixed populations. Here, we aimed to explore whether genetic ancestry was associated with asthma or related traits in the Canary Islanders. For that, a total of 734 DNA samples from unrelated individuals of the GOA study, self-reporting at least two generations of ancestors from the Canary Islands (391 asthmatics and 343 controls), were successfully genotyped for 83 ancestry informative markers (AIMs), which allowed to precisely distinguishing between North African and Iberian ancestries. No association was found between genetic ancestry and asthma or related traits after adjusting by demographic variables differing among compared groups. Similarly, none of the individual AIMs was associated with asthma when results were considered in the context of the multiple comparisons performed (0.005 ≤ p value ≤ 0.042; 0.221 ≤ q value ≤ 0.443). Our results suggest that if genetic ancestry were involved in the susceptibility to asthma or related traits among Canary Islanders, its effects would be modest. Larger studies, examining more genetic variants, would be needed to explore such possibility. PMID:22710824

  7. Socioeconomic and nutritional factors account for the association of gastric cancer with Amerindian ancestry in a Latin American admixed population.

    Directory of Open Access Journals (Sweden)

    Latife Pereira

    Full Text Available Gastric cancer is one of the most lethal types of cancer and its incidence varies worldwide, with the Andean region of South America showing high incidence rates. We evaluated the genetic structure of the population from Lima (Peru and performed a case-control genetic association study to test the contribution of African, European, or Native American ancestry to risk for gastric cancer, controlling for the effect of non-genetic factors. A wide set of socioeconomic, dietary, and clinic information was collected for each participant in the study and ancestry was estimated based on 103 ancestry informative markers. Although the urban population from Lima is usually considered as mestizo (i.e., admixed from Africans, Europeans, and Native Americans, we observed a high fraction of Native American ancestry (78.4% for the cases and 74.6% for the controls and a very low African ancestry (<5%. We determined that higher Native American individual ancestry is associated with gastric cancer, but socioeconomic factors associated both with gastric cancer and Native American ethnicity account for this association. Therefore, the high incidence of gastric cancer in Peru does not seem to be related to susceptibility alleles common in this population. Instead, our result suggests a predominant role for ethnic-associated socioeconomic factors and disparities in access to health services. Since Native Americans are a neglected group in genomic studies, we suggest that the population from Lima and other large cities from Western South America with high Native American ancestry background may be convenient targets for epidemiological studies focused on this ethnic group.

  8. European Ancestry Predominates in Neuromyelitis Optica and Multiple Sclerosis Patients from Brazil

    Science.gov (United States)

    Santos, Antônio Carlos; Lana-Peixoto, Marco Aurélio; Rocha, Cristiane Franklin; Brito, Maria Lucia; de Oliveira, Enedina Maria Lobato; Bichuetti, Denis Bernardi; Gabbai, Alberto Alan; Diniz, Denise Sisterolli; Kaimen-Maciel, Damacio Ramon; Comini-Frota, Elizabeth Regina; Vieira Wiezel, Claudia E.; Muniz, Yara Costa Netto; da Silva Costa, Roberta Martins; Mendes-Junior, Celso Teixeira; Donadi, Eduardo Antônio; Barreira, Amilton Antunes; Simões, Aguinaldo Luiz

    2013-01-01

    Background Neuromyelitis optica (NMO) is considered relatively more common in non-Whites, whereas multiple sclerosis (MS) presents a high prevalence rate, particularly in Whites from Western countries populations. However, no study has used ancestry informative markers (AIMs) to estimate the genetic ancestry contribution to NMO patients. Methods Twelve AIMs were selected based on the large allele frequency differences among European, African, and Amerindian populations, in order to investigate the genetic contribution of each ancestral group in 236 patients with MS and NMO, diagnosed using the McDonald and Wingerchuck criteria, respectively. All 128 MS patients were recruited at the Faculty of Medicine of Ribeirão Preto (MS-RP), Southeastern Brazil, as well as 108 healthy bone marrow donors considered as healthy controls. A total of 108 NMO patients were recruited from five Neurology centers from different Brazilian regions, including Ribeirão Preto (NMO-RP). Principal Findings European ancestry contribution was higher in MS-RP than in NMO-RP (78.5% vs. 68.7%) patients. In contrast, African ancestry estimates were higher in NMO-RP than in MS-RP (20.5% vs. 12.5%) patients. Moreover, principal component analyses showed that groups of NMO patients from different Brazilian regions were clustered close to the European ancestral population. Conclusions Our findings demonstrate that European genetic contribution predominates in NMO and MS patients from Brazil. PMID:23527051

  9. European ancestry predominates in neuromyelitis optica and multiple sclerosis patients from Brazil.

    Directory of Open Access Journals (Sweden)

    Doralina Guimarães Brum

    Full Text Available BACKGROUND: Neuromyelitis optica (NMO is considered relatively more common in non-Whites, whereas multiple sclerosis (MS presents a high prevalence rate, particularly in Whites from Western countries populations. However, no study has used ancestry informative markers (AIMs to estimate the genetic ancestry contribution to NMO patients. METHODS: Twelve AIMs were selected based on the large allele frequency differences among European, African, and Amerindian populations, in order to investigate the genetic contribution of each ancestral group in 236 patients with MS and NMO, diagnosed using the McDonald and Wingerchuck criteria, respectively. All 128 MS patients were recruited at the Faculty of Medicine of Ribeirão Preto (MS-RP, Southeastern Brazil, as well as 108 healthy bone marrow donors considered as healthy controls. A total of 108 NMO patients were recruited from five Neurology centers from different Brazilian regions, including Ribeirão Preto (NMO-RP. PRINCIPAL FINDINGS: European ancestry contribution was higher in MS-RP than in NMO-RP (78.5% vs. 68.7% patients. In contrast, African ancestry estimates were higher in NMO-RP than in MS-RP (20.5% vs. 12.5% patients. Moreover, principal component analyses showed that groups of NMO patients from different Brazilian regions were clustered close to the European ancestral population. CONCLUSIONS: Our findings demonstrate that European genetic contribution predominates in NMO and MS patients from Brazil.

  10. Quantification of Maxillary Dental Arcade Curvature and the Estimation of Biological Ancestry in Forensic Anthropology.

    Science.gov (United States)

    Clark, Melissa A; Guatelli-Steinberg, Debbie; Hubbe, Mark; Stout, Sam

    2016-01-01

    Previous studies suggest that palate shape is a useful indicator of biological ancestry in human remains. This study evaluates interobserver error in ancestry estimation using palate shape and explores palate shape variation in Gullah (descendants of West Africans) and Seminole (Indigenous American) population samples using geometric morphometric analysis. Ten participants were asked to ascribe biological ancestry and shape to 28 dental casts based on a classification scheme employed in previous studies. The mean correct classification was 42.0%, indicating that the likelihood of assigning the correct ancestry is very poor and not significantly different from random assignment (p = 0.12). The accuracy analysis based on categorical classification of the casts was complemented by geometric morphometric analysis of nine 3D landmarks reflecting palate shape of 158 casts. Principal component analysis results show no difference between populations regarding palate shape, and cross-validated discriminant function analysis correctly classified only 62.0% of the specimens. Combined, these results show that previous methods to estimate ancestry are inaccurate and that this inaccuracy is probably due to a lack of palate shape differences between groups, rather than limitation of the analytical method per se. Therefore, we recommend caution should be used when choosing to apply the analysis of palate shape in forensically relevant contexts. PMID:26259114

  11. Comprehensive Analysis of Pan-African Mitochondrial DNA Variation Provides New Insights into Continental Variation and Demography.

    Science.gov (United States)

    Cerezo, María; Gusmão, Leonor; Černý, Viktor; Uddin, Nabeel; Syndercombe-Court, Denise; Gómez-Carballa, Alberto; Göbel, Tanja; Schneider, Peter M; Salas, Antonio

    2016-03-20

    Africa is the cradle of all human beings, and although it has been the focus of a number of genetic studies, there are many questions that remain unresolved. We have performed one of the largest and most comprehensive meta-analyses of mitochondrial DNA (mtDNA) lineages carried out in the African continent to date. We generated high-throughput mtDNA single nucleotide polymorphism (SNP) data (230 SNPs) from 2024 Africans, where more than 500 of them were additionally genotyped for the control region. These data were analyzed together with over 12,700 control region profiles collected from the literature, representing more than 300 population samples from Africa. Insights into the African homeland of humans are discussed. Phylogeographic patterns for the African continent are shown at a high phylogeographic resolution as well as at the population and regional levels. The deepest branch of the mtDNA tree, haplogroup L0, shows the highest sub-haplogroup diversity in Southeast and East Africa, suggesting this region as the homeland for modern humans. Several demographic estimates point to the coast as a facilitator of human migration in Africa, but the data indicate complex patterns, perhaps mirroring the effect of recent continental-scaled demographic events in re-shaping African mtDNA variability. PMID:27020033

  12. Genetic ancestry analysis in non-alcoholic fatty liver diseasepatients from Brazil and Portuga

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    to those with S. Steatosis from each cohort(Brazilian cohort: P = 0.75; Portuguese cohort: P =0.97). Nonetheless, the genetic ancestry contribution ofthe Brazilian and Portuguese population were different,and a greater European and Amerindian ancestrycontribution was detected in the Portuguese populationwhile a higher African genetic ancestry contribution wasobserved in Brazilian population of both NASH and S.Steatosis groups.CONCLUSION: There was no difference betweenthe genetic ancestry contribution among Brazilian andPortuguese individuals with NASH and S. Steatosis fromeach cohort.

  13. CPAFFC Working Group Attends Sino-African Initiative Conference

    Institute of Scientific and Technical Information of China (English)

    Duan; Jun

    2013-01-01

    <正>A CPAFFC working group led by its Vice President Xie Yuan attended the 2013 Sino-African Initiative (SAI) Conference sponsored by Sister Cities International (SCI) of the United States and organized by the Eastern Africa Sister Cities (EASC) in Nairobi, Kenya, from January 31 to February 2. About 60 officials and representatives of sister cities associations from China, the United States, Kenya, Nigeria and

  14. African and non-African admixture components in African Americans and an African Caribbean population.

    Science.gov (United States)

    Murray, Tanda; Beaty, Terri H; Mathias, Rasika A; Rafaels, Nicholas; Grant, Audrey Virginia; Faruque, Mezbah U; Watson, Harold R; Ruczinski, Ingo; Dunston, Georgia M; Barnes, Kathleen C

    2010-09-01

    Admixture is a potential source of confounding in genetic association studies, so it becomes important to detect and estimate admixture in a sample of unrelated individuals. Populations of African descent in the US and the Caribbean share similar historical backgrounds but the distributions of African admixture may differ. We selected 416 ancestry informative markers (AIMs) to estimate and compare admixture proportions using STRUCTURE in 906 unrelated African Americans (AAs) and 294 Barbadians (ACs) from a study of asthma. This analysis showed AAs on average were 72.5% African, 19.6% European and 8% Asian, while ACs were 77.4% African, 15.9% European, and 6.7% Asian which were significantly different. A principal components analysis based on these AIMs yielded one primary eigenvector that explained 54.04% of the variation and captured a gradient from West African to European admixture. This principal component was highly correlated with African vs. European ancestry as estimated by STRUCTURE (r(2)=0.992, r(2)=0.912, respectively). To investigate other African contributions to African American and Barbadian admixture, we performed PCA on approximately 14,000 (14k) genome-wide SNPs in AAs, ACs, Yorubans, Luhya and Maasai African groups, and estimated genetic distances (F(ST)). We found AAs and ACs were closest genetically (F(ST)=0.008), and both were closer to the Yorubans than the other East African populations. In our sample of individuals of African descent, approximately 400 well-defined AIMs were just as good for detecting substructure as approximately 14,000 random SNPs drawn from a genome-wide panel of markers. PMID:20717976

  15. Multiple loci associated with renal function in African Americans.

    Directory of Open Access Journals (Sweden)

    Daniel Shriner

    Full Text Available The incidence of chronic kidney disease varies by ethnic group in the USA, with African Americans displaying a two-fold higher rate than European Americans. One of the two defining variables underlying staging of chronic kidney disease is the glomerular filtration rate. Meta-analysis in individuals of European ancestry has identified 23 genetic loci associated with the estimated glomerular filtration rate (eGFR. We conducted a follow-up study of these 23 genetic loci using a population-based sample of 1,018 unrelated admixed African Americans. We included in our follow-up study two variants in APOL1 associated with end-stage kidney disease discovered by admixture mapping in admixed African Americans. To address confounding due to admixture, we estimated local ancestry at each marker and global ancestry. We performed regression analysis stratified by local ancestry and combined the resulting regression estimates across ancestry strata using an inverse variance-weighted fixed effects model. We found that 11 of the 24 loci were significantly associated with eGFR in our sample. The effect size estimates were not significantly different between the subgroups of individuals with two copies of African ancestry vs. two copies of European ancestry for any of the 11 loci. In contrast, allele frequencies were significantly different at 10 of the 11 loci. Collectively, the 11 loci, including four secondary signals revealed by conditional analyses, explained 14.2% of the phenotypic variance in eGFR, in contrast to the 1.4% explained by the 24 loci in individuals of European ancestry. Our findings provide insight into the genetic basis of variation in renal function among admixed African Americans.

  16. The Lord’s Resistance Army: an African Terrorist Group?

    OpenAIRE

    Emma Leonard

    2011-01-01

    The years since 9/11 have been characterised by the increasing threat of terrorist action in the  Middle East and South Asia. Yet Sub-Saharan Africa was has also become a region of concern. In 1998, it had been the scene of two Al-Qaeda attacks against US embassies; besides Africa is home to large Muslim populations. Since 9/11 African violent non-state groups unrelated to Al- Qaeda or to the wider Islamist movement have been recast as terrorist organisations. These groups primarily oper...

  17. Pacifiplex: an ancestry-informative SNP panel centred on Australia and the Pacific region.

    Science.gov (United States)

    Santos, Carla; Phillips, Christopher; Fondevila, Manuel; Daniel, Runa; van Oorschot, Roland A H; Burchard, Esteban G; Schanfield, Moses S; Souto, Luis; Uacyisrael, Jolame; Via, Marc; Carracedo, Ángel; Lareu, Maria V

    2016-01-01

    The analysis of human population variation is an area of considerable interest in the forensic, medical genetics and anthropological fields. Several forensic single nucleotide polymorphism (SNP) assays provide ancestry-informative genotypes in sensitive tests designed to work with limited DNA samples, including a 34-SNP multiplex differentiating African, European and East Asian ancestries. Although assays capable of differentiating Oceanian ancestry at a global scale have become available, this study describes markers compiled specifically for differentiation of Oceanian populations. A sensitive multiplex assay, termed Pacifiplex, was developed and optimized in a small-scale test applicable to forensic analyses. The Pacifiplex assay comprises 29 ancestry-informative marker SNPs (AIM-SNPs) selected to complement the 34-plex test, that in a combined set distinguish Africans, Europeans, East Asians and Oceanians. Nine Pacific region study populations were genotyped with both SNP assays, then compared to four reference population groups from the HGDP-CEPH human diversity panel. STRUCTURE analyses estimated population cluster membership proportions that aligned with the patterns of variation suggested for each study population's currently inferred demographic histories. Aboriginal Taiwanese and Philippine samples indicated high East Asian ancestry components, Papua New Guinean and Aboriginal Australians samples were predominantly Oceanian, while other populations displayed cluster patterns explained by the distribution of divergence amongst Melanesians, Polynesians and Micronesians. Genotype data from Pacifiplex and 34-plex tests is particularly well suited to analysis of Australian Aboriginal populations and when combined with Y and mitochondrial DNA variation will provide a powerful set of markers for ancestry inference applied to modern Australian demographic profiles. On a broader geographic scale, Pacifiplex adds highly informative data for inferring the ancestry

  18. Sediment Dynamics off the East African Continental Margin during the Last Deglaciation and the Holocene: Constrained by Changes in Climate and Sea Level

    OpenAIRE

    Liu, Xiting

    2014-01-01

    This thesis focused on sediment dynamics on the East African continental margin and their response to paleoclimatic and sea-level changes on a millennial time scale during the last deglaciation and Holocene. High-resolution Holocene sedimentary records (core GeoB12605-3) from the continental shelf off Tanzania indicate that that there has been a shift in the sedimentation regime during the past 10 ka. During the early Holocene, when climate was humid, sediments were dominated by the allochtho...

  19. Single-Nucleotide Polymorphisms in LPA Explain Most of the Ancestry-Specific Variation in Lp(a) Levels in African Americans

    OpenAIRE

    Deo, Rahul C.; Wilson, James G; Xing, Chao; Lawson, Kim; Kao, W.H. Linda; Reich, David; Tandon, Arti; Akylbekova, Ermeg; Patterson, Nick; Mosley, Thomas H (Jr); Boerwinkle, Eric; Taylor, Herman A.

    2011-01-01

    Lipoprotein(a) (Lp(a)) is an important causal cardiovascular risk factor, with serum Lp(a) levels predicting atherosclerotic heart disease and genetic determinants of Lp(a) levels showing association with myocardial infarction. Lp(a) levels vary widely between populations, with African-derived populations having nearly 2-fold higher Lp(a) levels than European Americans. We investigated the genetic basis of this difference in 4464 African Americans from the Jackson Heart Study (JHS) using a pa...

  20. Continental islands - the biogeography of the East African forest-dwelling mountain rodent Praomys delectorum

    Czech Academy of Sciences Publication Activity Database

    Patzenhauerová, Hana; Matur, Ferhat; Mikula, Ondřej; Šumbera, R.; Verheyen, E.; Chitaukali, W. N.; Bryja, Josef

    Kwaluseni: University of Swaziland, 2011. s. 32. [African Small Mammal Symposium /11./. 03.08.2011-08.08.2011, Kwaluseni] Institutional research plan: CEZ:AV0Z60930519 Keywords : Praomys delectorum * biogeography * Eastern Africa Subject RIV: EG - Zoology

  1. The Lord’s Resistance Army: an African Terrorist Group?

    Directory of Open Access Journals (Sweden)

    Emma Leonard

    2011-01-01

    Full Text Available The years since 9/11 have been characterised by the increasing threat of terrorist action in the  Middle East and South Asia. Yet Sub-Saharan Africa was has also become a region of concern. In 1998, it had been the scene of two Al-Qaeda attacks against US embassies; besides Africa is home to large Muslim populations. Since 9/11 African violent non-state groups unrelated to Al- Qaeda or to the wider Islamist movement have been recast as terrorist organisations. These groups primarily operate in conflict zones, an area of research that traditionally has not been the main focus of Terrorism Studies. Protagonists have at various times been called freedom fighters, rebels, warlords, insurgents or simply violent gangs. This article looks at the most notorious of African groups – the Lord’s Resistance Army (LRA. It argues that some groups like the LRA have been recast as terrorist organisations not because of a change in their activities but due to a change in the geo-strategic environment they found themselves in the post-9/11 period. The LRA’s ideology and tactics will be judged against a broad definition of terrorism in order to test whether the group can, in an objective way, be called a terrorist organisation. It is concluded that the LRA is too ambiguous an organisation to be simply labelled in such a way. It is also suggested that the terrorism label has in fact been an obstacle to attempts to end successfully a confrontation that is now going into its 24th year. 

  2. Principles of Geological Mapping of Marine Sediments (with Special Reference to the African Continental Margin). Unesco Reports in Marine Science No. 37.

    Science.gov (United States)

    Lisitzin, Alexandre P.

    Designed to serve as a complement to the Unesco Technical Papers in Marine Science, this report concentrates on theoretical and practical problems of geological mapping of the sea floor. An introduction is given to geological mapping procedures at continental margins as well as some practical recommendations taking as an example the African region…

  3. Male ancestry structure and interethnic admixture in African-descent communities from the Amazon as revealed by Y-chromosome Strs.

    Science.gov (United States)

    Palha, Teresinha de Jesus Brabo Ferreira; Ribeiro-Rodrigues, Elzemar Martins; Ribeiro-dos-Santos, Andrea; Guerreiro, João Farias; de Moura, Luciene Soraya Souza; Santos, Sidney

    2011-03-01

    Some genetic markers on both the Y chromosome and mtDNA are highly polymorphic and population-specific in humans, representing useful tools for reconstructing the past history of populations with poor historical records. Such lack of information is usually true in the case of recent African-descent populations of the New World founded by fugitive slaves throughout the slavery period in the Americas, particularly in Brazil, where those communities are known as quilombos. Aiming to recover male-derived ethnic structure of nine quilombos from the Brazilian Amazon, a total of 300 individuals, belonging to Mazagão Velho (N = 24), Curiaú (N = 48), Mazagão (N = 36), Trombetas (N = 20), Itacoã (N = 22), Saracura (N = 46), Marajó (N = 58), Pitimandeua (N = 26), and Pontal (N = 20), were investigated for nine Y-STRs (DYS393, DYS19, DYS390, DYS389 I, DYS389 II, DYS392, DYS391, DYS385 I/II). From the 169 distinct haplotypes obtained, 120 were singletons. The results suggest the West African coast as the main origin of slaves brought to Brazil (54% of male contribution); the European contribution was high (41%), while the Amerindian's was low (5%). Those results contrast with previous mtDNA data that showed high Amerindian female contribution (46.6%) in African-descent populations. AMOVA suggests that the genetic differentiation among the quilombos is mainly influenced by admixture with European. However, when restricting AMOVA to African-specific haplotypes, low differentiation was detected, suggesting great genetic homogeneity of the African founding populations and/or a later homogenization by intense slave trade inside Brazil. PMID:21302273

  4. Gravity study of the Central African Rift system: A model of continental disruption 1. The Ngaoundere and Abu Gabra Rifts

    Science.gov (United States)

    Browne, S. E.; Fairhead, J. D.

    1983-05-01

    A regional compilation of published and unpublished gravity data for Central Africa is presented and reveals the presence of a major rift system, called here, the Central African Rift System. It is proposed that the junction area between the Ngaoundere and Abu Gabra rift arms in Western Sudan forms an incipient intraplate, triple-junction with the as yet unfractured, but domally uplifted and volcanically active, Darfur swell. It is only the Darfur swell that shows any similarities to the uplift and rift history of East Africa. The other two rifts arms are considered to be structurally similar to the early stages of passive margin development and thus reflect more closely the initial processes of continental fragmentation than the structures associated with rifting in East Africa.

  5. Mitochondrial and Y chromosome haplotype motifs as diagnostic markers of Jewish ancestry: a reconsideration

    Science.gov (United States)

    Tofanelli, Sergio; Taglioli, Luca; Bertoncini, Stefania; Francalacci, Paolo; Klyosov, Anatole; Pagani, Luca

    2014-01-01

    Several authors have proposed haplotype motifs based on site variants at the mitochondrial genome (mtDNA) and the non-recombining portion of the Y chromosome (NRY) to trace the genealogies of Jewish people. Here, we analyzed their main approaches and test the feasibility of adopting motifs as ancestry markers through construction of a large database of mtDNA and NRY haplotypes from public genetic genealogical repositories. We verified the reliability of Jewish ancestry prediction based on the Cohen and Levite Modal Haplotypes in their “classical” 6 STR marker format or in the “extended” 12 STR format, as well as four founder mtDNA lineages (HVS-I segments) accounting for about 40% of the current population of Ashkenazi Jews. For this purpose we compared haplotype composition in individuals of self-reported Jewish ancestry with the rest of European, African or Middle Eastern samples, to test for non-random association of ethno-geographic groups and haplotypes. Overall, NRY and mtDNA based motifs, previously reported to differentiate between groups, were found to be more represented in Jewish compared to non-Jewish groups. However, this seems to stem from common ancestors of Jewish lineages being rather recent respect to ancestors of non-Jewish lineages with the same “haplotype signatures.” Moreover, the polyphyly of haplotypes which contain the proposed motifs and the misuse of constant mutation rates heavily affected previous attempts to correctly dating the origin of common ancestries. Accordingly, our results stress the limitations of using the above haplotype motifs as reliable Jewish ancestry predictors and show its inadequacy for forensic or genealogical purposes. PMID:25431579

  6. Frequencies of HID-ion ampliseq ancestry panel markers among greenlanders

    DEFF Research Database (Denmark)

    Espregueira Themudo, Gonçalo; Smidt Mogensen, Helle; Børsting, Claus;

    2016-01-01

    The HID-Ion AmpliSeq Ancestry Panel from Life Techologies includes 123 SNPs from the Seldin panel and 55 SNPs from Kidd panel in a single multiplex assay that helps to determine the continental biogeographic ancestry of individuals. We tested the panel on 104 Greenlanders, divided into a training...

  7. Southern African continental climate since the late Pleistocene: Insights from biomarker analyses of Kalahari salt pan sediments

    Science.gov (United States)

    Belz, Lukas; Schüller, Irka; Wehrmann, Achim; Wilkes, Heinz

    2016-04-01

    The climate system of sub-tropical southern Africa is mainly controlled by large scale atmospheric and marine circulation processes and, therefore, very sensitive to global climate change. This underlines the importance of paleoenvironmental reconstructions in order to estimate regional implications of current global changes. However, the majority of studies on southern African paleoclimate are based on the investigation of marine sedimentary archives and past climate development especially in continental areas is still poorly understood. This emphasizes the necessity of continental proxy-data from this area. Proxy datasets from local geoarchives especially of the southwestern Kalahari region are still scarce. A main problem is the absence of conventional continental climatic archives, due to the lack of lacustrine systems. In this study we are exploring the utility of sediments from western Kalahari salt pans, i.e. local depressions which are flooded temporarily during rainfall events. An age model based on 14C dating of total organic carbon (TOC) shows evidence that sedimentation predominates over erosional processes with respect to pan formation. Besides the analyses of basic geochemical bulk parameters including TOC, δ13CTOC, total inorganic carbon, δ13CTIC, δ18OTIC, total nitrogen and δ15N, our paleo-climatic approach focuses on reconstruction of local vegetation assemblages to identify changes in the ecosystem. This is pursued using plant biomarkers, particularly leaf wax n-alkanes and n-alcohols and their stable carbon and hydrogen isotopic signatures. Results show prominent shifts in n-alkane and n-alkanol distributions and compound specific carbon isotope values, pointing to changes to a more grass dominated environment during Heinrich Stadial 1 (18.5-14.6 ka BP), while hydrogen isotope values suggest wetter phases during Holocene and LGM. This high variability indicates the local vulnerability to global change.

  8. A continental analysis of correlations between tree patterns in African savannas and human and environmental variables

    NARCIS (Netherlands)

    Groen, T.A.; Langevelde, van F.; Vijver, van de C.A.D.M.; Raad, de A.L.; Leeuw, de J.; Prins, H.H.T.

    2011-01-01

    This study analyses possible relationships between natural processes taking place in savannas and the tree patterns found in savannas. This can lead to new hypotheses about which processes are driving savanna physiognomy. To do so tree patterns were quantified for African savannas from historical ae

  9. Inter-laboratory evaluation of the EUROFORGEN Global ancestry-informative SNP panel by massively parallel sequencing using the Ion PGM™

    DEFF Research Database (Denmark)

    Eduardoff, M; Gross, T E; Santos, C;

    2016-01-01

    the exclusion of component SNP rs2080161 from the Global AIM-SNPs panel. However, the overall genotyping precision and sensitivity of this custom multiplex indicates the Ion PGM™ assay for the Global AIM-SNPs is highly suitable for forensic ancestry analysis with massively parallel sequencing.......The EUROFORGEN Global ancestry-informative SNP (AIM-SNPs) panel is a forensic multiplex of 128 markers designed to differentiate an individual's ancestry from amongst the five continental population groups of Africa, Europe, East Asia, Native America, and Oceania. A custom multiplex of Ampli......Seq™ PCR primers was designed for the Global AIM-SNPs to perform massively parallel sequencing using the Ion PGM™ system. This study assessed individual SNP genotyping precision using the Ion PGM™, the forensic sensitivity of the multiplex using dilution series, degraded DNA plus simple mixtures, and the...

  10. Genomics assisted ancestry deconvolution in grape.

    Directory of Open Access Journals (Sweden)

    Jason Sawler

    Full Text Available The genus Vitis (the grapevine is a group of highly diverse, diploid woody perennial vines consisting of approximately 60 species from across the northern hemisphere. It is the world's most valuable horticultural crop with ~8 million hectares planted, most of which is processed into wine. To gain insights into the use of wild Vitis species during the past century of interspecific grape breeding and to provide a foundation for marker-assisted breeding programmes, we present a principal components analysis (PCA based ancestry estimation method to calculate admixture proportions of hybrid grapes in the United States Department of Agriculture grape germplasm collection using genome-wide polymorphism data. We find that grape breeders have backcrossed to both the domesticated V. vinifera and wild Vitis species and that reasonably accurate genome-wide ancestry estimation can be performed on interspecific Vitis hybrids using a panel of fewer than 50 ancestry informative markers (AIMs. We compare measures of ancestry informativeness used in selecting SNP panels for two-way admixture estimation, and verify the accuracy of our method on simulated populations of admixed offspring. Our method of ancestry deconvolution provides a first step towards selection at the seed or seedling stage for desirable admixture profiles, which will facilitate marker-assisted breeding that aims to introgress traits from wild Vitis species while retaining the desirable characteristics of elite V. vinifera cultivars.

  11. Taxonomic revision of the tropical African group of Carex subsect. Elatae (sect. Spirostachyae, Cyperaceae

    Directory of Open Access Journals (Sweden)

    Escudero, Marcial

    2011-12-01

    Full Text Available The tropical African monophyletic group of Carex subsect. Elatae (sect. Spirostachyae is distributed in continental tropical Africa, Madagascar, the Mascarene archipelago, and Bioko Island (32 km off the coast of West Africa, in the Gulf of Guinea. The first monographic treatment of this Carex group, as well as of the tribe Cariceae, was published by Kükenthal (as sect. Elatae Kük.. Recently, the first molecular (nrDNA, cpDNA phylogeny of Carex sect. Elatae has been published, which also included the species of sect. Spirostachyae. In the resulting consensus trees, most species of sect. Elatae were embedded within core Spirostachyae and so this section was joined with sect. Spirostachyae as subsect. Elatae. Within subsect. Elatae, several groups were described, one of which was termed the “tropical African group”. Here we present a taxonomic revision of this group, based on more than 280 vouchers from 29 herbaria as well as in field trips in Tropical Africa. In the revision, we recognise 12 species (16 taxa within the tropical African group, and so have somewhat modified our previous view, in which 10 species, 12 taxa were listed. One new species from Tanzania is included in this treatment, C. uluguruensis Luceño & M. Escudero. Several combinations are made, C. cyrtosaccus is treated as a synonym of C. vallis-rosetto and, finally, the binomial C. greenwayi has been recognised.Las especies de la subsección Elatae (sección Spirostachyae del género Carex que se distribuyen por África tropical continental, Madagascar, el archipiélago de las Mascareñas y la isla de Bioko (a 32 km del litoral de África occidental, en el golfo de Guinea forman un grupo monofilético. El primer tratamiento taxonómico de este grupo de cárices, así como de la tribu Cariceae en su conjunto, fue elaborado por Kükenthal (sección Elatae Kük.; recientemente, se ha publicado el primer estudio de filogenia molecular (nrDNA, cpDNA de los táxones de este grupo

  12. Inter-laboratory evaluation of the EUROFORGEN Global ancestry-informative SNP panel by massively parallel sequencing using the Ion PGM™.

    Science.gov (United States)

    Eduardoff, M; Gross, T E; Santos, C; de la Puente, M; Ballard, D; Strobl, C; Børsting, C; Morling, N; Fusco, L; Hussing, C; Egyed, B; Souto, L; Uacyisrael, J; Syndercombe Court, D; Carracedo, Á; Lareu, M V; Schneider, P M; Parson, W; Phillips, C; Parson, W; Phillips, C

    2016-07-01

    The EUROFORGEN Global ancestry-informative SNP (AIM-SNPs) panel is a forensic multiplex of 128 markers designed to differentiate an individual's ancestry from amongst the five continental population groups of Africa, Europe, East Asia, Native America, and Oceania. A custom multiplex of AmpliSeq™ PCR primers was designed for the Global AIM-SNPs to perform massively parallel sequencing using the Ion PGM™ system. This study assessed individual SNP genotyping precision using the Ion PGM™, the forensic sensitivity of the multiplex using dilution series, degraded DNA plus simple mixtures, and the ancestry differentiation power of the final panel design, which required substitution of three original ancestry-informative SNPs with alternatives. Fourteen populations that had not been previously analyzed were genotyped using the custom multiplex and these studies allowed assessment of genotyping performance by comparison of data across five laboratories. Results indicate a low level of genotyping error can still occur from sequence misalignment caused by homopolymeric tracts close to the target SNP, despite careful scrutiny of candidate SNPs at the design stage. Such sequence misalignment required the exclusion of component SNP rs2080161 from the Global AIM-SNPs panel. However, the overall genotyping precision and sensitivity of this custom multiplex indicates the Ion PGM™ assay for the Global AIM-SNPs is highly suitable for forensic ancestry analysis with massively parallel sequencing. PMID:27208666

  13. Building a forensic ancestry panel from the ground up

    DEFF Research Database (Denmark)

    Phillips, C; Parson, W; Lundsberg, Birgitte Møller;

    2014-01-01

    Emerging next-generation sequencing technologies will enable DNA analyses to add pigmentation predictive and ancestry informative (AIM) SNPs to the range of markers detectable from a single PCR test. This prompted us to re-appraise current forensic and genomics AIM-SNPs and from the best sets...... to minimize bias when estimating co-ancestry proportions in individuals with admixed ancestries. The differentiation of European from Middle East or South Asian ancestries was not chosen as a characteristic in order to concentrate on introducing Oceanian differentiation for the first time in a forensic AIM......-specific divergence in at least four groups. We describe subsets of 88, 55, 28, 20 and 12 AIMs, enabling both new and existing SNP genotyping technologies to exploit the best markers identified for forensic ancestry analysis....

  14. Crustal structure variations along the NW-African continental margin: A comparison of new and existing models from wide-angle and reflection seismic data

    Science.gov (United States)

    Klingelhoefer, Frauke; Biari, Youssef; Sahabi, Mohamed; Aslanian, Daniel; Schnabel, Michael; Matias, Luis; Benabdellouahed, Massinissa; Funck, Thomas; Gutscher, Marc-André; Reichert, Christian; Austin, James A.

    2016-04-01

    Deep seismic data represent a key to understand the geometry and mechanism of continental rifting. The passive continental margin of NW-Africa is one of the oldest on earth, formed during the Upper Triassic-Lower Liassic rifting of the central Atlantic Ocean over 200 Ma. We present new and existing wide-angle and reflection seismic data from four study regions along the margin located in the south offshore DAKHLA, on the central continental margin offshore Safi, in the northern Moroccan salt basin, and in the Gulf of Cadiz. The thickness of unthinned continental crust decreases from 36 km in the North to about 27 km in the South. Crustal thinning takes place over a region of 150 km in the north and only 70 km in the south. The North Moroccan Basin is underlain by highly thinned continental crust of only 6-8 km thickness. The ocean-continent transition zone shows a variable width between 40 and 70 km and is characterized by seismic velocities in between those of typical oceanic and thinned continental crust. The neighbouring oceanic crust is characterized by a thickness of 7-8 km along the complete margin. Relatively high velocities of up to 7.5 km/s have been imaged between magnetic anomalies S1 and M25, and are probably related to changes in the spreading velocities at the time of the Kimmeridgian/Tithonian plate reorganization. Volcanic activity seems to be mostly confined to the region next to the Canary Islands, and is thus not related to the initial opening of the ocean, which was associated to only weak volcanism. Comparison with the conjugate margin off Nova Scotia shows comparable continental crustal structures, but 2-3 km thinner oceanic crust on the American side than on the African margin.

  15. What Ancestry Can Tell Us About the Genetic Origins of Inter-Ethnic Differences in Asthma Expression.

    Science.gov (United States)

    Hernandez-Pacheco, Natalia; Flores, Carlos; Oh, Sam S; Burchard, Esteban G; Pino-Yanes, Maria

    2016-07-01

    Differences in asthma prevalence have been described across different populations, suggesting that genetic ancestry can play an important role in this disease. In fact, several studies have demonstrated an association between African ancestry with increased asthma susceptibility and severity, higher immunoglobulin E levels, and lower lung function. In contrast, Native American ancestry has been shown to have a protective role for this disease. Genome-wide association studies have allowed the identification of population-specific genetic variants with varying allele frequency among populations. Additionally, the correlation of genetic ancestry at the chromosomal level with asthma and related traits by means of admixture mapping has revealed regions of the genome where ancestry is correlated with the disease. In this review, we discuss the evidence supporting the association of genetic ancestry with asthma susceptibility and asthma-related traits, and highlight the regions of the genome harboring ancestry-specific genetic risk factors. PMID:27393700

  16. Helicobacter pylori genotyping from American indigenous groups shows novel Amerindian vacA and cagA alleles and Asian, African and European admixture.

    Directory of Open Access Journals (Sweden)

    Margarita Camorlinga-Ponce

    Full Text Available It is valuable to extend genotyping studies of Helicobacter pylori to strains from indigenous communities across the world to better define adaption, evolution, and associated diseases. We aimed to genetically characterize both human individuals and their infecting H. pylori from indigenous communities of Mexico, and to compare them with those from other human groups. We studied individuals from three indigenous groups, Tarahumaras from the North, Huichols from the West and Nahuas from the center of Mexico. Volunteers were sampled at their community site, DNA was isolated from white blood cells and mtDNA, Y-chromosome, and STR alleles were studied. H. pylori was cultured from gastric juice, and DNA extracted for genotyping of virulence and housekeeping genes. We found Amerindian mtDNA haplogroups (A, B, C, and D, Y-chromosome DYS19T, and Amerindian STRs alleles frequent in the three groups, confirming Amerindian ancestry in these Mexican groups. Concerning H.pylori cagA phylogenetic analyses, although most isolates were of the Western type, a new Amerindian cluster neither Western nor Asian, was formed by some indigenous Mexican, Colombian, Peruvian and Venezuelan isolates. Similarly, vacA phylogenetic analyses showed the existence of a novel Amerindian type in isolates from Alaska, Mexico and Colombia. With hspA strains from Mexico and other American groups clustered within the three major groups, Asian, African or European. Genotyping of housekeeping genes confirmed that Mexican strains formed a novel Asian-related Amerindian group together with strains from remote Amazon Aborigines. This study shows that Mexican indigenous people with Amerindian markers are colonized with H. pylori showing admixture of Asian, European and African strains in genes known to interact with the gastric mucosa. We present evidence of novel Amerindian cagA and vacA alleles in indigenous groups of North and South America.

  17. Neither self-reported ethnicity nor declared family origin are reliable indicators of genomic ancestry.

    Science.gov (United States)

    Ramos, Bruna Ribeiro de Andrade; D'Elia, Maria Paula Barbieri; Amador, Marcos Antônio Trindade; Santos, Ney Pereira Carneiro; Santos, Sidney Emanuel Batista; da Cruz Castelli, Erick; Witkin, Steven S; Miot, Hélio Amante; Miot, Luciane Donida Bartoli; da Silva, Márcia Guimarães

    2016-06-01

    Ancestry information can be useful in investigations of diseases with a genetic or infectious background. As the Brazilian population is highly admixed physical traits tend to be poor indicators of ancestry. The assessment of ancestry by ancestry informative markers (AIMs) can exclude the subjectivity of self-declared ethnicity and reported family origin. We aimed to evaluate the reliability of self-reported ethnicity or reported family origin as indicators of genomic ancestry in a female population from the Southeast of Brazil. Two cohorts were included: 404 women asked to self-report their ethnicity (Pop1) and 234 women asked to report their family's origin (Pop2). Identification of AIMs was performed using a panel of 61 markers and results were plotted against parental populations-Amerindian, Western European and Sub-Saharan African-using Structure v2.3.4. In Pop1 57.4 % of women self-reported as white, 34.6 % as brown and 8.0 % as black. Median global European, Amerindian and African contributions were 66.8, 12.6 and 16.6 %. In Pop2, 66.4 % of women declared European origin, 23.9 % African origin and 26.9 % Amerindian. Median global European, Amerindian and African contributions were 80.8, 7.3 and 7.6 %, respectively. Only 31.0 and 21.0 % of the global variation in African and European contributions, respectively, could be explained by self-reported ethnicity and reported family origin only accounted for 20.0 and 5.0 % of the variations observed in African and European ancestries, respectively. Amerindian ancestry did not influence self-reported ethnicity or declared family origin. Neither self-reported ethnicity nor declared family origin are reliable indicators of genomic ancestry in these Brazilian populations. PMID:26984822

  18. Exploring the Y Chromosomal Ancestry of Modern Panamanians.

    Directory of Open Access Journals (Sweden)

    Viola Grugni

    Full Text Available Geologically, Panama belongs to the Central American land-bridge between North and South America crossed by Homo sapiens >14 ka ago. Archaeologically, it belongs to a wider Isthmo-Colombian Area. Today, seven indigenous ethnic groups account for 12.3% of Panama's population. Five speak Chibchan languages and are characterized by low genetic diversity and a high level of differentiation. In addition, no evidence of differential structuring between maternally and paternally inherited genes has been reported in isthmian Chibchan cultural groups. Recent data have shown that 83% of the Panamanian general population harbour mitochondrial DNAs (mtDNAs of Native American ancestry. Considering differential male/female mortality at European contact and multiple degrees of geographical and genetic isolation over the subsequent five centuries, the Y-chromosome Native American component is expected to vary across different geographic regions and communities in Panama. To address this issue, we investigated Y-chromosome variation in 408 modern males from the nine provinces of Panama and one indigenous territory (the comarca of Kuna Yala. In contrast to mtDNA data, the Y-chromosome Native American component (haplogroup Q exceeds 50% only in three populations facing the Caribbean Sea: the comarca of Kuna Yala and Bocas del Toro province where Chibchan languages are spoken by the majority, and the province of Colón where many Kuna and people of mixed indigenous-African-and-European descent live. Elsewhere the Old World component is dominant and mostly represented by western Eurasian haplogroups, which signal the strong male genetic impact of invaders. Sub-Saharan African input accounts for 5.9% of male haplotypes. This reflects the consequences of the colonial Atlantic slave trade and more recent influxes of West Indians of African heritage. Overall, our findings reveal a local evolution of the male Native American ancestral gene pool, and a strong but

  19. Exploring the Y Chromosomal Ancestry of Modern Panamanians.

    Science.gov (United States)

    Grugni, Viola; Battaglia, Vincenza; Perego, Ugo Alessandro; Raveane, Alessandro; Lancioni, Hovirag; Olivieri, Anna; Ferretti, Luca; Woodward, Scott R; Pascale, Juan Miguel; Cooke, Richard; Myres, Natalie; Motta, Jorge; Torroni, Antonio; Achilli, Alessandro; Semino, Ornella

    2015-01-01

    Geologically, Panama belongs to the Central American land-bridge between North and South America crossed by Homo sapiens >14 ka ago. Archaeologically, it belongs to a wider Isthmo-Colombian Area. Today, seven indigenous ethnic groups account for 12.3% of Panama's population. Five speak Chibchan languages and are characterized by low genetic diversity and a high level of differentiation. In addition, no evidence of differential structuring between maternally and paternally inherited genes has been reported in isthmian Chibchan cultural groups. Recent data have shown that 83% of the Panamanian general population harbour mitochondrial DNAs (mtDNAs) of Native American ancestry. Considering differential male/female mortality at European contact and multiple degrees of geographical and genetic isolation over the subsequent five centuries, the Y-chromosome Native American component is expected to vary across different geographic regions and communities in Panama. To address this issue, we investigated Y-chromosome variation in 408 modern males from the nine provinces of Panama and one indigenous territory (the comarca of Kuna Yala). In contrast to mtDNA data, the Y-chromosome Native American component (haplogroup Q) exceeds 50% only in three populations facing the Caribbean Sea: the comarca of Kuna Yala and Bocas del Toro province where Chibchan languages are spoken by the majority, and the province of Colón where many Kuna and people of mixed indigenous-African-and-European descent live. Elsewhere the Old World component is dominant and mostly represented by western Eurasian haplogroups, which signal the strong male genetic impact of invaders. Sub-Saharan African input accounts for 5.9% of male haplotypes. This reflects the consequences of the colonial Atlantic slave trade and more recent influxes of West Indians of African heritage. Overall, our findings reveal a local evolution of the male Native American ancestral gene pool, and a strong but geographically

  20. African American and European American Students' Peer Groups during Early Adolescence: Structure, Status, and Academic Achievement

    Science.gov (United States)

    Wilson, Travis; Karimpour, Ramin; Rodkin, Philip C.

    2011-01-01

    Focusing on a sample of 382 African American (206 female) and 264 European American (132 female) students in diverse fourth and fifth grade classrooms, this study investigated three questions concerning the connections between peer groups and academic achievement during early adolescence: (a) How is group structure (i.e., hierarchy and cohesion)…

  1. Ancestry Analysis in the 11-M Madrid Bomb Attack Investigation

    OpenAIRE

    Christopher Phillips; Lourdes Prieto; Manuel Fondevila; Antonio Salas; Antonio Gómez-Tato; José Alvarez-Dios; Antonio Alonso; Alejandro Blanco-Verea; María Brión; Marta Montesino; Angel Carracedo; María Victoria Lareu

    2009-01-01

    The 11-M Madrid commuter train bombings of 2004 constituted the second biggest terrorist attack to occur in Europe after Lockerbie, while the subsequent investigation became the most complex and wide-ranging forensic case in Spain. Standard short tandem repeat (STR) profiling of 600 exhibits left certain key incriminatory samples unmatched to any of the apprehended suspects. A judicial order to perform analyses of unmatched samples to differentiate European and North African ancestry became a...

  2. 76 FR 46209 - Importation of Tomatoes From the Economic Community of West African States Into the Continental...

    Science.gov (United States)

    2011-08-02

    ... Plant Health Inspection Service (APHIS) amend the regulations to allow fresh tomatoes (Solanum..., titled ``Importation of Tomatoes, Solanum lycopersicum, from the Economic Community of West African... certain countries. * * * * * (h) Tomatoes (fruit) (Solanum lycopersicum) from member States of...

  3. Associations of PON1 and genetic ancestry with obesity in early childhood.

    Directory of Open Access Journals (Sweden)

    Karen Huen

    Full Text Available Obesity in children has become an epidemic in the U.S. and is particularly prominent in minority populations such as Mexican-Americans. In addition to physical activity and diet, genetics also plays a role in obesity etiology. A few studies in adults and adolescents suggest a link between obesity and paraoxonase 1 (PON1, a multifunctional enzyme that can metabolize organophosphate pesticides and also has antioxidant properties. We determined PON1192 genotype and arylesterase levels (ARYase, measure of PON1 enzyme quantity, to characterize the relationship between PON1 and obesity in young Mexican-American children (n = 373 living in an agricultural community in California. Since PON1 polymorphisms and obesity both vary between ethnic groups, we estimated proportional genetic ancestry using 106 ancestral informative markers (AIMs. Among children, PON1192 allele frequencies were 0.5 for both alleles, and the prevalence of obesity was high (15% and 33% at ages two and five, respectively. The average proportion of European, African, and Native American ancestry was 0.40, 0.09, and 0.51, yet there was wide inter-individual variation. We found a significantly higher odds of obesity (9.3 and 2.5- fold in PON1192QQ children compared to PON1192RR children at ages two and five, respectively. Similar relationships were seen with BMI Z-scores at age two and waist circumference at age five. After adjusting for genetic ancestry in models of PON1 and BMI Z-score, effect estimates for PON1192 genotype changed 15% and 9% among two and five year old children, respectively, providing evidence of genetic confounding by population stratification. However even after adjustment for genetic ancestry, the trend of increased BMI Z-scores with increased number of PON1192 Q alleles remained. Our findings suggest that PON1 may play a role in obesity independent of genetic ancestry and that studies of PON1 and health outcomes, especially in admixed populations, should

  4. An assessment of the portability of ancestry informative markers between human populations

    Directory of Open Access Journals (Sweden)

    Stoneking Mark

    2009-07-01

    Full Text Available Abstract Background Recent work has shown that population stratification can have confounding effects on genetic association studies and statistical methods have been developed to correct for these effects. Subsets of markers that are highly-differentiated between populations, ancestry-informative markers (AIMs, have been used to correct for population stratification. Often AIMs are discovered in one set of populations and then employed in a different set of populations. The underlying assumption in these cases is that the population under study has the same substructure as the population in which the AIMs were discovered. The present study assesses this assumption and evaluates the portability between worldwide populations of 10 SNPs found to be highly-differentiated within Britain (BritAIMs. Methods We genotyped 10 BritAIMs in ~1000 individuals from 53 populations worldwide. We assessed the degree to which these 10 BritAIMs capture population stratification in other groups of populations by use of the Fst statistic. We used Fst values from 2750 random markers typed in the same set of individuals as an empirical distribution to which the Fst values of the 10 BritAIMs were compared. Results Allele frequency differences between continental groups for the BritAIMs are not unusually high. This is also the case for comparisons within continental groups distantly related to Britain. However, two BritAIMs show high Fst between European populations and two BritAIMs show high Fst between populations from the Middle East. Overall the median Fst across all BritAIMs is not unusually high compared to the empirical distribution. Conclusion We find that BritAIMs are generally not useful to distinguish between continental groups or within continental groups distantly related to Britain. Moreover, our analyses suggest that the portability of AIMs across geographical scales (e.g. between Europe and Britain can be limited and should therefore be taken into

  5. Evolution of the African continental crust as recorded by U-Pb, Lu-Hf and O isotopes in detrital zircons from modern rivers

    Science.gov (United States)

    Iizuka, Tsuyoshi; Campbell, Ian H.; Allen, Charlotte M.; Gill, James B.; Maruyama, Shigenori; Makoka, Frédéric

    2013-04-01

    To better understand the evolutionary history of the African continental crust, a combined U-Pb, Lu-Hf and O isotopic study has been carried out by in situ analyses of approximately 450 detrital zircon grains from the Niger, Nile, Congo, Zambezi and Orange Rivers. The U-Pb isotopic data show age peaks at ca. 2.7, 2.1-1.8, 1.2-1.0, ca. 0.8, 0.7-0.5 and ca. 0.3 Ga. These peaks, with the exception of the one at ca. 0.8 Ga, correspond with the assembly of supercontinents. Furthermore, the detrital zircons that crystallized during these periods of supercontinent assembly have dominantly non-mantle-like O and Hf isotopic signatures, in contrast to the ca. 0.8 Ga detrital zircons which have juvenile characteristics. These data can be interpreted as showing that continental collisions during supercontinent assembly resulted in supermountain building accompanied by remelting of older continental crust, which in turn led to significant erosion of young igneous rocks with non-mantle-like isotopic signatures. Alternatively, the data may indicate that the major mode of crustal development changed during the supercontinent cycle: the generation of juvenile crust in extensional settings was dominant during supercontinent fragmentation, whereas the stabilization of the generated crust via crustal accretion and reworking was important during supercontinent assembly. The Lu-Hf and O isotope systematics indicate that terreigneous sediments could attain elevated 18O/16O via prolonged sediment-sediment recycling over long crustal residence time, and also that reworking of carbonate and chert which generally have elevated 18O/16O and low Hf contents is minor in granitoid magmatism. The highest 18O/16O in detrital zircon abruptly increased at ca. 2.1 Ga and became nearly constant thereafter. This indicates that reworking of mature sediments increased abruptly at that time, probably as a result of a transition in the dynamics of either granitoid crust formation or sedimentary evolution

  6. Assessment in multicultural groups: The South African case

    Directory of Open Access Journals (Sweden)

    A. J. R. Van De Vijver

    2004-10-01

    Full Text Available It is argued that the 1998 Employment Equity Act, in which the onus of the proof to demonstrate the adequacy of psychometric instruments is on psychology as a profession, creates daunting tasks, but also creates unique opportunities. Recent developments in the assessment of multicultural groups are described, with an emphasis on procedures to enhance the validity of measures for all groups involved and on procedures to examine validity. Bias and equivalence are treated as key concepts in multicultural assessment. Four kinds of procedures for dealing with multicultural assessment (namely, establishing equivalence of existing instruments, defining new norms, developing new instruments, and studying validity-threatening factors in multicultural assessment are described and illustrated. Opsomming Daar word geredeneer dat die Wet op Billike Indiensneming, 1998, waarvolgens die onus om die geskiktheid van psigometriese instrumente te bewys na psigologie as professie verskuif, nie net oorweldigende take nie maar ook unieke geleenthede skep. Onlangse ontwikkelings rakende die evaluering van multikulturele groepe word beskryf, met die klem op prosedures om die geldigheid van metings vir alle groepe te verhoog en op prosedures om hierdie geldigheid te ondersoek. Sydigheid en ekwivalensie word as sleutelkonsepte in multikulturele evaluering behandel. Vier soorte prosedures om multikulturele evaluering te hanteer (te wete bepaling van die ekwivalensie van bestaande instrumente, definiëring van nuwe norme, ontwikkeling van nuwe instrumente en ‘n studie van faktore wat die geldigheid van multikulturele evaluering bedreig word beskryf en geïllustreer.

  7. Men of African Descent and Carcinoma of the Prostate Consortium

    Science.gov (United States)

    The Men of African Descent and Carcinoma of the Prostate Consortium collaborates on epidemiologic studies to address the high burden of prostate cancer and to understand the causes of etiology and outcomes among men of African ancestry.

  8. Forensic ancestry analysis with two capillary electrophoresis ancestry informative marker (AIM) panels

    DEFF Research Database (Denmark)

    Santos, C; Fondevila, M; Ballard, D;

    2015-01-01

    There is increasing interest in forensic ancestry tests, which are part of a growing number of DNA analyses that can enhance routine profiling by obtaining additional genetic information about unidentified DNA donors. Nearly all ancestry tests use single nucleotide polymorphisms (SNPs), but these...... relationship between input DNA and signal strength as each marker is detected with a single dye, so mixed DNA is more reliably detected. We report the results of a collaborative inter-laboratory exercise of 19 participants (15 from the EDNAP European DNA Profiling group) that assessed a 34-plex SNP test using...... DNA mixture as well as achieving complete and concordant profiles in nearly all cases. Lastly, two participants successfully ran parallel next-generation sequencing analyses (each using different systems) and achieved high levels of genotyping concordance using the exercise PCR primer mixes unmodified....

  9. What Is Genetic Ancestry Testing?

    Science.gov (United States)

    ... type of test because Y chromosome and mitochondrial DNA test results, which represent only single ancestral lines, do ... relationships. On a larger scale, combined genetic ancestry test results from many people can be used ... promotes the use of DNA testing in genealogy. The American Society of Human ...

  10. Variation in APOL1 Contributes to Ancestry-Level Differences in HDLc-Kidney Function Association

    Directory of Open Access Journals (Sweden)

    Amy Rebecca Bentley

    2012-01-01

    Full Text Available Low levels of high-density cholesterol (HDLc accompany chronic kidney disease, but the association between HDLc and the estimated glomerular filtration rate (eGFR in the general population is unclear. We investigated the HDLc-eGFR association in nondiabetic Han Chinese (HC, n=1100, West Africans (WA, n=1497, and African Americans (AA, n=1539. There were significant differences by ancestry: HDLc was positively associated with eGFR in HC (β=0.13, P<0.0001, but negatively associated among African ancestry populations (WA: −0.19, P<0.0001; AA: −0.09, P=0.02. These differences were also seen in nationally-representative NHANES data (among European Americans: 0.09, P=0.005; among African Americans −0.14, P=0.03. To further explore the findings in African ancestry populations, we investigated the role of an African ancestry-specific nephropathy risk variant, rs73885319, in the gene encoding HDL-associated APOL1. Among AA, an inverse HDLc-eGFR association was observed only with the risk genotype (−0.38 versus 0.001; P=0.03. This interaction was not seen in WA. In summary, counter to expectation, an inverse HDLc-eGFR association was observed among those of African ancestry. Given the APOL1 × HDLc interaction among AA, genetic factors may contribute to this paradoxical association. Notably, these findings suggest that the unexplained mechanism by which APOL1 affects kidney-disease risk may involve HDLc.

  11. Higher levels of neanderthal ancestry in East Asians than in Europeans.

    Science.gov (United States)

    Wall, Jeffrey D; Yang, Melinda A; Jay, Flora; Kim, Sung K; Durand, Eric Y; Stevison, Laurie S; Gignoux, Christopher; Woerner, August; Hammer, Michael F; Slatkin, Montgomery

    2013-05-01

    Neanderthals were a group of archaic hominins that occupied most of Europe and parts of Western Asia from ∼30,000 to 300,000 years ago (KYA). They coexisted with modern humans during part of this time. Previous genetic analyses that compared a draft sequence of the Neanderthal genome with genomes of several modern humans concluded that Neanderthals made a small (1-4%) contribution to the gene pools of all non-African populations. This observation was consistent with a single episode of admixture from Neanderthals into the ancestors of all non-Africans when the two groups coexisted in the Middle East 50-80 KYA. We examined the relationship between Neanderthals and modern humans in greater detail by applying two complementary methods to the published draft Neanderthal genome and an expanded set of high-coverage modern human genome sequences. We find that, consistent with the recent finding of Meyer et al. (2012), Neanderthals contributed more DNA to modern East Asians than to modern Europeans. Furthermore we find that the Maasai of East Africa have a small but significant fraction of Neanderthal DNA. Because our analysis is of several genomic samples from each modern human population considered, we are able to document the extent of variation in Neanderthal ancestry within and among populations. Our results combined with those previously published show that a more complex model of admixture between Neanderthals and modern humans is necessary to account for the different levels of Neanderthal ancestry among human populations. In particular, at least some Neanderthal-modern human admixture must postdate the separation of the ancestors of modern European and modern East Asian populations. PMID:23410836

  12. [South African tick bite fever in a group of Russian tourists].

    Science.gov (United States)

    Kozhevnikova, G M; Tokmalaev, A K; Voznesensky, S L; Karan, L S

    2014-01-01

    The paper describes a clinical case of South African tick bite fever in a group of Russian tourists. The group of 5 people who had been ill with this disease after a tourist trip to the South African Republic (the Kruger National Park in the north-eastern province of Mpumalanga) were followed up. During their trip, all of them were bitten by different insects many times. The disease exhibited different clinical presentations; however, all the patients were noted to have a fever with slight intoxication and a maculopapular rash at different sites of the body; 3 had lymphadenopathy and one had a primary effect at the site of tick sticking. The diagnosis was verified by indirect immunofluorescence for the detection of high titers to Rickettsia conorii. The course of the disease was favorable in all the patients treated with antibiotics (doxycycline or ceftriaxone). PMID:25715493

  13. Exploring the Musical Culture of an African American Child with Developmental Disabilities in Group Music Therapy

    Directory of Open Access Journals (Sweden)

    Meghan Cork

    2013-07-01

    Full Text Available The purpose of this study was to explore the role of the musical culture of an African American child with developmental disabilities in group music therapy. Qualitative methods were employed in an early childhood education setting. First, interview questions were sent home to parents and guardians of participants regarding music in the home, and music examples were analyzed based on the genres reported in the interview answers. Then, one session of four male participants with developmental disabilities, ages 4-5, was conducted and analyzed. The participants were of African American, Hispanic, Pakistani, and Caucasian ethnicities. The researcher focused on the African American child, utilizing clinical data and an examination of the musical sources that represent the child’s musical culture in the home. The results indicated that the musical culture of the child played a significant role in the group music therapy process. The musical culture of the African American child in the study was found to be characterized by three main elements: emphasis on a strong rhythmic pulse, emphasis on movement, and singing or chanting as a means of expression. The child seemed to be less engaged when the music was syncopated, lacked a strong rhythmic pulse, was interspersed with verbal injections, or contained Spanish lyrics. Although some conclusions have been drawn to indicate the significance of musical culture in a group music therapy setting with children, there is a great need for further research in order to determine more precise ways in which musical culture influences the group music therapy process. Thus, this study serves as a catalyst for future music therapy research.

  14. Exploring the Musical Culture of an African American Child with Developmental Disabilities in Group Music Therapy

    OpenAIRE

    Meghan Cork

    2013-01-01

    The purpose of this study was to explore the role of the musical culture of an African American child with developmental disabilities in group music therapy. Qualitative methods were employed in an early childhood education setting. First, interview questions were sent home to parents and guardians of participants regarding music in the home, and music examples were analyzed based on the genres reported in the interview answers. Then, one session of four male participants with developmental d...

  15. Why do some South African ethnic groups have very high HIV rates and others not?

    Science.gov (United States)

    Kenyon, Chris; Zondo, Sizwe

    2011-04-01

    The differences in HIV prevalence between South Africa's racial/ethnic groups (19.9%, 3.2%, and 0.5% among 15-49-year-old blacks, coloureds and whites, respectively) are as big as those between the countries with the highest and lowest levels of HIV prevalence worldwide. These large racial/ethnic differences are largely determined by different sexual network structures. In networks among black South Africans, sexual partnerships are more likely to be arranged concurrently - a configuration that leads to exponential increases in the spread of HIV. An examination of the historical origins of polygamy (where it is normative for partnerships to be arranged concurrently) and monogamy (serial or lifetime) reveals that it is the practice of universal monogamy in stratified societies which is the outlier. The ideology and practice of universal monogamy originated in Europe as the result of several factors, most prominently conflicts between the Christian Church and the nobility. After its imposition in Europe, the European colonial project would see this ideology disseminated around the world. Under the influence of liberalism it would mutate into a secular and unacknowledged value-programme of monogamy as a universal norm. This value-programme and practice of monogamy (mostly serial) is still the norm for white South Africans; thus, this sexual behaviour 'spandrel' (by-product of other historical processes) is a large contributor to the lower levels of HIV prevalence among whites. In pre-colonial African societies, polygyny was normative, and the Christian value-programme of monogamy never achieved the hegemonic status it did in Europe and other areas of conquest. Married black African men who converted to Christianity were no less likely to have additional sexual partners, but only more likely to conceal them. The ongoing secrecy about having concurrent partners has contributed to the connectedness of sexual networks among black Africans at large and in this manner has

  16. Expert groups in Denmark with special reference to Classical and African swine fever

    DEFF Research Database (Denmark)

    Uttenthal, Åse

    2012-01-01

    The Danish (National Veterinary) Expert group for Classical and African swine fever has been active during the last 10 years. The group is composed of experts in EU-legislation, in Danish pig production, in pig diseases and in virology. The group has participated in a national workshop on CSFV...... surveillance, in Contingency planning exercises and many efforts is done to keep the group updated on the current international situation for swine fevers. The group has been very stabile and especially our participation in a Taiex workshop in 2005 in Romania was a very good basis for our fruitful...... collaboration. In many later discussions our experiences then when we observed the problems in vivo. The obligations of the expert group are both to follow the progress of eradication but definitely also to take care of some of the more time consuming discussions that could otherwise burden the Veterinary...

  17. Biogeographic Ancestry, Self-Identified Race, and Admixture-Phenotype Associations in the Heart SCORE Study

    OpenAIRE

    Halder, Indrani; Kip, Kevin E.; Mulukutla, Suresh R.; Aiyer, Aryan N.; Marroquin, Oscar C; Huggins, Gordon S.; Reis, Steven E.

    2012-01-01

    Large epidemiologic studies examining differences in cardiovascular disease (CVD) risk factor profiles between European Americans and African Americans have exclusively used self-identified race (SIR) to classify individuals. Recent genetic epidemiology studies of some CVD risk factors have suggested that biogeographic ancestry (BGA) may be a better predictor of CVD risk than SIR. This hypothesis was investigated in 464 African Americans and 771 European Americans enrolled in the Heart Strate...

  18. Regional differences in awareness and attitudes regarding genetic testing for disease risk and ancestry.

    Science.gov (United States)

    Jonassaint, Charles R; Santos, Eunice R; Glover, Crystal M; Payne, Perry W; Fasaye, Grace-Ann; Oji-Njideka, Nefertiti; Hooker, Stanley; Hernandez, Wenndy; Foster, Morris W; Kittles, Rick A; Royal, Charmaine D

    2010-09-01

    Little is known about the lay public's awareness and attitudes concerning genetic testing and what factors influence their perspectives. The existing literature focuses mainly on ethnic and socioeconomic differences; however, here we focus on how awareness and attitudes regarding genetic testing differ by geographical regions in the US. We compared awareness and attitudes concerning genetic testing for disease risk and ancestry among 452 adults (41% Black and 67% female) in four major US cities, Norman, OK; Cincinnati, OH; Harlem, NY; and Washington, DC; prior to their participation in genetic ancestry testing. The OK participants reported more detail about their personal ancestries (p = 0.02) and valued ancestry testing over disease testing more than all other sites (p < 0.01). The NY participants were more likely than other sites to seek genetic testing for disease (p = 0.01) and to see benefit in finding out more about one's ancestry (p = 0.02), while the DC participants reported reading and hearing more about genetic testing for African ancestry than all other sites (p < 0.01). These site differences were not better accounted for by sex, age, education, self-reported ethnicity, religion, or previous experience with genetic testing/counseling. Regional differences in awareness and attitudes transcend traditional demographic predictors, such as ethnicity, age and education. Local sociocultural factors, more than ethnicity and socioeconomic status, may influence the public's awareness and belief systems, particularly with respect to genetics. PMID:20549517

  19. Biogeographic ancestry, self-identified race, and admixture-phenotype associations in the Heart SCORE Study.

    Science.gov (United States)

    Halder, Indrani; Kip, Kevin E; Mulukutla, Suresh R; Aiyer, Aryan N; Marroquin, Oscar C; Huggins, Gordon S; Reis, Steven E

    2012-07-15

    Large epidemiologic studies examining differences in cardiovascular disease (CVD) risk factor profiles between European Americans and African Americans have exclusively used self-identified race (SIR) to classify individuals. Recent genetic epidemiology studies of some CVD risk factors have suggested that biogeographic ancestry (BGA) may be a better predictor of CVD risk than SIR. This hypothesis was investigated in 464 African Americans and 771 European Americans enrolled in the Heart Strategies Concentrating on Risk Evaluation (Heart SCORE) Study in March and April 2010. Individual West African and European BGA were ascertained by means of a panel of 1,595 genetic ancestry informative markers. Individual BGA varied significantly among African Americans and to a lesser extent among European Americans. In the total cohort, BGA was not found to be a better predictor of CVD risk factors than SIR. Both measures predicted differences in the presence of the metabolic syndrome, waist circumference, triglycerides, body mass index, very low density lipoprotein cholesterol, lipoprotein A, and systolic and diastolic blood pressure between European Americans and African Americans. These results suggest that for most nongenetic cardiovascular epidemiology studies, SIR is sufficient for predicting CVD risk factor differences between European Americans and African Americans. However, higher body mass index and diastolic blood pressure were significantly associated with West African BGA among African Americans, suggesting that BGA should be considered in genetic cardiovascular epidemiology studies carried out among African Americans. PMID:22771727

  20. Ancestry analysis in the 11-M Madrid bomb attack investigation.

    Directory of Open Access Journals (Sweden)

    Christopher Phillips

    Full Text Available The 11-M Madrid commuter train bombings of 2004 constituted the second biggest terrorist attack to occur in Europe after Lockerbie, while the subsequent investigation became the most complex and wide-ranging forensic case in Spain. Standard short tandem repeat (STR profiling of 600 exhibits left certain key incriminatory samples unmatched to any of the apprehended suspects. A judicial order to perform analyses of unmatched samples to differentiate European and North African ancestry became a critical part of the investigation and was instigated to help refine the search for further suspects. Although mitochondrial DNA (mtDNA and Y-chromosome markers routinely demonstrate informative geographic differentiation, the populations compared in this analysis were known to show a proportion of shared mtDNA and Y haplotypes as a result of recent gene-flow across the western Mediterranean, while any two loci can be unrepresentative of the ancestry of an individual as a whole. We based our principal analysis on a validated 34plex autosomal ancestry-informative-marker single nucleotide polymorphism (AIM-SNP assay to make an assignment of ancestry for DNA from seven unmatched case samples including a handprint from a bag containing undetonated explosives together with personal items recovered from various locations in Madrid associated with the suspects. To assess marker informativeness before genotyping, we predicted the probable classification success for the 34plex assay with standard error estimators for a naïve Bayesian classifier using Moroccan and Spanish training sets (each n = 48. Once misclassification error was found to be sufficiently low, genotyping yielded seven near-complete profiles (33 of 34 AIM-SNPs that in four cases gave probabilities providing a clear assignment of ancestry. One of the suspects predicted to be North African by AIM-SNP analysis of DNA from a toothbrush was identified late in the investigation as Algerian in origin. The

  1. Gravity study of the Central African Rift system: a model of continental disruption 2. The Darfur domal uplift and associated Cainozoic volcanism

    Science.gov (United States)

    Bermingham, P. M.; Fairhead, J. D.; Stuart, G. W.

    1983-05-01

    Gravity studies of the Darfur uplift, Western Sudan, show it to be associated with a circular negative Bouguer anomaly, 50 mGal in amplitude and 700 km across. A three-dimensional model interpretation of the Darfur anomaly, using constraints deduced from geophysical studies of similar but more evolved Kenya and Ethiopia domes, suggests either a low-density laccolithic body at mid-lithospheric depth (~ 60 km) or a thinned lithosphere with emplacement at high level of low-density asthenospheric material. The regional setting of the Darfur uplift is described in terms of it being an integral part of the Central African Rift System which is shown to be broadly equivalent to the early to middle Miocene stage in the development of the Afro-Arabian Rift System. Comparisons between these rift systems suggest that extensional tectonics and passive rifting, resulting in the subsiding sedimentary rift basins associated with the Ngaoundere, Abu Gabra, Red Sea and Gulf of Aden rifts, are more typical of the early stage development of passive continental margins than the active domal uplift and development of rifted features associated with the Darfur, Kenya and Ethiopia domes.

  2. Forensic ancestry analysis with two capillary electrophoresis ancestry informative marker (AIM) panels: Results of a collaborative EDNAP exercise.

    Science.gov (United States)

    Santos, C; Fondevila, M; Ballard, D; Banemann, R; Bento, A M; Børsting, C; Branicki, W; Brisighelli, F; Burrington, M; Capal, T; Chaitanya, L; Daniel, R; Decroyer, V; England, R; Gettings, K B; Gross, T E; Haas, C; Harteveld, J; Hoff-Olsen, P; Hoffmann, A; Kayser, M; Kohler, P; Linacre, A; Mayr-Eduardoff, M; McGovern, C; Morling, N; O'Donnell, G; Parson, W; Pascali, V L; Porto, M J; Roseth, A; Schneider, P M; Sijen, T; Stenzl, V; Court, D Syndercombe; Templeton, J E; Turanska, M; Vallone, P M; van Oorschot, R A H; Zatkalikova, L; Carracedo, Á; Phillips, C

    2015-11-01

    There is increasing interest in forensic ancestry tests, which are part of a growing number of DNA analyses that can enhance routine profiling by obtaining additional genetic information about unidentified DNA donors. Nearly all ancestry tests use single nucleotide polymorphisms (SNPs), but these currently rely on SNaPshot single base extension chemistry that can fail to detect mixed DNA. Insertion-deletion polymorphism (Indel) tests have been developed using dye-labeled primers that allow direct capillary electrophoresis detection of PCR products (PCR-to-CE). PCR-to-CE maintains the direct relationship between input DNA and signal strength as each marker is detected with a single dye, so mixed DNA is more reliably detected. We report the results of a collaborative inter-laboratory exercise of 19 participants (15 from the EDNAP European DNA Profiling group) that assessed a 34-plex SNP test using SNaPshot and a 46-plex Indel test using PCR-to-CE. Laboratories were asked to type five samples with different ancestries and detect an additional mixed DNA sample. Statistical inference of ancestry was made by participants using the Snipper online Bayes analysis portal plus an optional PCA module that analyzes the genotype data alongside calculation of Bayes likelihood ratios. Exercise results indicated consistent genotyping performance from both tests, reaching a particularly high level of reliability for the Indel test. SNP genotyping gave 93.5% concordance (compared to the organizing laboratory's data) that rose to 97.3% excluding one laboratory with a large number of miscalled genotypes. Indel genotyping gave a higher concordance rate of 99.8% and a reduced no-call rate compared to SNP analysis. All participants detected the mixture from their Indel peak height data and successfully assigned the correct ancestry to the other samples using Snipper, with the exception of one laboratory with SNP miscalls that incorrectly assigned ancestry of two samples and did not obtain

  3. Mosaic maternal ancestry in the Great Lakes region of East Africa.

    Science.gov (United States)

    Gomes, Verónica; Pala, Maria; Salas, Antonio; Álvarez-Iglesias, Vanesa; Amorim, António; Gómez-Carballa, Alberto; Carracedo, Ángel; Clarke, Douglas J; Hill, Catherine; Mormina, Maru; Shaw, Marie-Anne; Dunne, David W; Pereira, Rui; Pereira, Vânia; Prata, Maria João; Sánchez-Diz, Paula; Rito, Teresa; Soares, Pedro; Gusmão, Leonor; Richards, Martin B

    2015-09-01

    The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago. PMID:26188410

  4. Methodological Considerations in Estimation of Phenotype Heritability Using Genome-Wide SNP Data, Illustrated by an Analysis of the Heritability of Height in a Large Sample of African Ancestry Adults

    OpenAIRE

    Chen, Fang; He, Jing; Zhang, Jianqi; Chen, Gary K.; Thomas, Venetta; Ambrosone, Christine B.; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; William J Blot; Cai, Qiuyin; Carpten, John; Casey, Graham; Chanock, Stephen J.; Cheng, Iona

    2015-01-01

    Height has an extremely polygenic pattern of inheritance. Genome-wide association studies (GWAS) have revealed hundreds of common variants that are associated with human height at genome-wide levels of significance. However, only a small fraction of phenotypic variation can be explained by the aggregate of these common variants. In a large study of African-American men and women (n = 14,419), we genotyped and analyzed 966,578 autosomal SNPs across the entire genome using a linear mixed model ...

  5. La oportunidad de un atlas sobre el estado del continente africano / The Opportunity of an Atlas about the Situation of the African Continent

    Directory of Open Access Journals (Sweden)

    Eva Pérez Hernández

    2014-12-01

    Full Text Available Desde la Antigüedad clásica hasta nuestros días se han multiplicado las representaciones cartográficas de la Tierra, sin embargo, no todos los territorios del planeta han recibido la misma atención. En el caso del continente africano son escasas las colecciones de mapas recientes y, especialmente, las que conforman atlas temáticos. Esta circunstancia fue determinante en la orientación de las prácticas desarrolladas en Casa África durante el curso académico 2012-2013, al amparo del Consorcio Casa África-Universidad de Las Palmas de Gran Canaria. El objetivo de las prácticas fue la elaboración de un atlas digital de África que tuvo como resultado la realización de cuarenta mapas temáticos basados en indicadores geográficos, ambientales, demográficos, económicos, sociales, geopolíticos, culturales y de sus relaciones económicas y políticas con España. La elaboración de dicho atlas se vio afectada por numerosas dificultades en cuanto a la búsqueda y tratamiento de las fuentes de información y por un trabajo de diseño y edición que requirió de la utilización de las nuevas tecnologías de la información geográfica. El presente artículo reflexiona acerca de la importancia de la cartografía como herramienta imprescindible de conocimiento geográfico y acerca de la superación de dificultades que entrañan retos como el de la realización de un atlas sobre el estado actual del continente africano.From Classical Antiquity to the present days, cartographic representations of the Earth have multiplied. However, not all the territories of the planet have received the same attention. In the case of the African continent, there are few collections of recent maps, especially, of those that are composed of thematic atlases. This circumstance was decisive in determining the focus of the internship in Casa África during academic year 2012-2013, under the auspices of the Consortium Casa África - University of Las Palmas de Gran

  6. The Impact of Perceived Group Support on the Effectiveness of an HIV Prevention Intervention for African American Women

    Science.gov (United States)

    Belgrave, Faye Z.; Corneille, Maya; Hood, Kristina; Foster-Woodson, Julia; Fitzgerald, Angela

    2010-01-01

    The enormous HIV/AIDS disparity among African American women and women in other ethnic groups dictates the need to implement the most effective HIV prevention interventions. This study examined the impact of perceived group support on HIV protective behaviors (i.e., attitudes and behaviors related to condom use, alcohol, and drugs) of African…

  7. Dating Violence and Sexual Assault Prevention with African American Middle Schoolers: Does Group Gender Composition Impact Dating Violence Attitudes?

    Science.gov (United States)

    Black, Beverly M.; Weisz, Arlene N.; Jayasundara, Dheeshana S.

    2012-01-01

    A dating violence and sexual assault prevention program was presented to 396, predominately African American, middle schoolers in two inner city schools in the United States. In one school the program was offered with a same-gender group composition; in the other school, the same program was offered with mixed-gender group composition. A…

  8. Admixture in Latin America: geographic structure, phenotypic diversity and self-perception of ancestry based on 7,342 individuals.

    Directory of Open Access Journals (Sweden)

    Andrés Ruiz-Linares

    2014-09-01

    Full Text Available The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú. These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry.

  9. Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals

    Science.gov (United States)

    Ruiz-Linares, Andrés; Adhikari, Kaustubh; Acuña-Alonzo, Victor; Quinto-Sanchez, Mirsha; Jaramillo, Claudia; Arias, William; Fuentes, Macarena; Pizarro, María; Everardo, Paola; de Avila, Francisco; Gómez-Valdés, Jorge; León-Mimila, Paola; Hunemeier, Tábita; Ramallo, Virginia; Silva de Cerqueira, Caio C.; Burley, Mari-Wyn; Konca, Esra; de Oliveira, Marcelo Zagonel; Veronez, Mauricio Roberto; Rubio-Codina, Marta; Attanasio, Orazio; Gibbon, Sahra; Ray, Nicolas; Gallo, Carla; Poletti, Giovanni; Rosique, Javier; Schuler-Faccini, Lavinia; Salzano, Francisco M.; Bortolini, Maria-Cátira; Canizales-Quinteros, Samuel; Rothhammer, Francisco; Bedoya, Gabriel; Balding, David; Gonzalez-José, Rolando

    2014-01-01

    The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú). These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry. PMID:25254375

  10. Additive opportunistic capture explains group hunting benefits in African wild dogs.

    Science.gov (United States)

    Hubel, Tatjana Y; Myatt, Julia P; Jordan, Neil R; Dewhirst, Oliver P; McNutt, J Weldon; Wilson, Alan M

    2016-01-01

    African wild dogs (Lycaon pictus) are described as highly collaborative endurance pursuit hunters based on observations derived primarily from the grass plains of East Africa. However, the remaining population of this endangered species mainly occupies mixed woodland savannah where hunting strategies appear to differ from those previously described. We used high-resolution GPS and inertial technology to record fine-scale movement of all members of a single pack of six adult African wild dogs in northern Botswana. The dogs used multiple short-distance hunting attempts with a low individual kill rate (15.5%), but high group feeding rate due to the sharing of prey. Use of high-level cooperative chase strategies (coordination and collaboration) was not recorded. In the mixed woodland habitats typical of their current range, simultaneous, opportunistic, short-distance chasing by dogs pursuing multiple prey (rather than long collaborative pursuits of single prey by multiple individuals) could be the key to their relative success in these habitats. PMID:27023355

  11. Admixture mapping of end stage kidney disease genetic susceptibility using estimated mutual information ancestry informative markers

    Directory of Open Access Journals (Sweden)

    Geiger Dan

    2010-10-01

    Full Text Available Abstract Background The question of a genetic contribution to the higher prevalence and incidence of end stage kidney disease (ESKD among African Americans (AA remained unresolved, until recent findings using admixture mapping pointed to the association of a genomic locus on chromosome 22 with this disease phenotype. In the current study we utilize this example to demonstrate the utility of applying a multi-step admixture mapping approach. Methods A multi-step case only admixture mapping study, consisted of the following steps was designed: 1 Assembly of the sample dataset (ESKD AA; 2 Design of the estimated mutual information ancestry informative markers (n = 2016 screening panel 3; Genotyping the sample set whose size was determined by a power analysis (n = 576 appropriate for the initial screening panel; 4 Inference of local ancestry for each individual and identification of regions with increased AA ancestry using two different ancestry inference statistical approaches; 5 Enrichment of the initial screening panel; 6 Power analysis of the enriched panel 7 Genotyping of additional samples. 8 Re-analysis of the genotyping results to identify a genetic risk locus. Results The initial screening phase yielded a significant peak using the ADMIXMAP ancestry inference program applying case only statistics. Subgroup analysis of 299 ESKD patients with no history of diabetes yielded peaks using both the ANCESTRYMAP and ADMIXMAP ancestry inference programs. The significant peak was found on chromosome 22. Genotyping of additional ancestry informative markers on chromosome 22 that took into account linkage disequilibrium in the ancestral populations, and the addition of samples increased the statistical significance of the finding. Conclusions A multi-step admixture mapping analysis of AA ESKD patients replicated the finding of a candidate risk locus on chromosome 22, contributing to the heightened susceptibility of African Americans to develop non

  12. Seasonal patterns of mixed species groups in large East African mammals.

    Science.gov (United States)

    Kiffner, Christian; Kioko, John; Leweri, Cecilia; Krause, Stefan

    2014-01-01

    Mixed mammal species groups are common in East African savannah ecosystems. Yet, it is largely unknown if co-occurrences of large mammals result from random processes or social preferences and if interspecific associations are consistent across ecosystems and seasons. Because species may exchange important information and services, understanding patterns and drivers of heterospecific interactions is crucial for advancing animal and community ecology. We recorded 5403 single and multi-species clusters in the Serengeti-Ngorongoro and Tarangire-Manyara ecosystems during dry and wet seasons and used social network analyses to detect patterns of species associations. We found statistically significant associations between multiple species and association patterns differed spatially and seasonally. Consistently, wildebeest and zebras preferred being associated with other species, whereas carnivores, African elephants, Maasai giraffes and Kirk's dik-diks avoided being in mixed groups. During the dry season, we found that the betweenness (a measure of importance in the flow of information or disease) of species did not differ from a random expectation based on species abundance. In contrast, in the wet season, we found that these patterns were not simply explained by variations in abundances, suggesting that heterospecific associations were actively formed. These seasonal differences in observed patterns suggest that interspecific associations may be driven by resource overlap when resources are limited and by resource partitioning or anti-predator advantages when resources are abundant. We discuss potential mechanisms that could drive seasonal variation in the cost-benefit tradeoffs that underpin the formation of mixed-species groups. PMID:25470495

  13. The construct equivalence of the job diagnostic survey for diverse South African cultural groups

    Directory of Open Access Journals (Sweden)

    M. Vorster

    2005-10-01

    Full Text Available The Job Diagnostic Survey (JDS and the Job Characteristics Model (JCM have been widely used in South African organisations. The purpose of this study was to determine whether the JDS is useful if it is applied to a particular population or to groups from highly dissimilar backgrounds. Cultural diversity research has revealed differences between the values, attitudes and leadership styles of people from different cultural groups. In this study, Hackman and Oldham’s JDS was applied to Black and White employees (n=66 to determine construct equivalence for these two cultural groups. Confirmatory factor analysis confirmed that there were no significant differences between the Black and White groups tested, suggesting that the JDS could be applied to different population groups. Opsomming Die Pos-diagnostiese vraelys (JDS en die Pos-kenmerke Model (JCM word wydverspreid deur Suid-Afrikaanse organisasies gebruik. Die doel van hierdie studie was om te bepaal of die JDS van toepassing is op verskillende kultuurgroepe. Navorsing rakende kultuurdiversiteit het aangetoon dat daar verskille bestaan rakende die waardes, houdings en leierskapstyle van verskillende kultuurgroepe. In hierdie studie is die (JDS van Hackman en Oldham toegepas op Swart- en Blanke werknemers (n=677 ten einde die konstruk-ekwivalensie daarvan bepaal. ’n Bevestigende faktorontleding het aangetoon dat daar geen betekenisvolle verskille bestaan tussen die Swart- en Blankegroepe wat getoets is nie. Die aanname word dus gemaak dat die JDS toegepas kan word op verskillende populasiegroepe.

  14. Genomic Insights into the Ancestry and Demographic History of South America.

    Directory of Open Access Journals (Sweden)

    Julian R Homburger

    2015-12-01

    Full Text Available South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9-14 generations ago, with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform

  15. Genomic Insights into the Ancestry and Demographic History of South America

    Science.gov (United States)

    Homburger, Julian R.; Moreno-Estrada, Andrés; Gignoux, Christopher R.; Nelson, Dominic; Sanchez, Elena; Ortiz-Tello, Patricia; Pons-Estel, Bernardo A.; Acevedo-Vasquez, Eduardo; Miranda, Pedro; Langefeld, Carl D.; Gravel, Simon; Alarcón-Riquelme, Marta E.; Bustamante, Carlos D.

    2015-01-01

    South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina) to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9–14 generations ago), with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform future medical

  16. Genomic Insights into the Ancestry and Demographic History of South America.

    Science.gov (United States)

    Homburger, Julian R; Moreno-Estrada, Andrés; Gignoux, Christopher R; Nelson, Dominic; Sanchez, Elena; Ortiz-Tello, Patricia; Pons-Estel, Bernardo A; Acevedo-Vasquez, Eduardo; Miranda, Pedro; Langefeld, Carl D; Gravel, Simon; Alarcón-Riquelme, Marta E; Bustamante, Carlos D

    2015-12-01

    South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina) to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9-14 generations ago), with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform future medical

  17. Head rubbing and licking reinforce social bonds in a group of captive African lions, Panthera leo.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Matoba

    Full Text Available Many social animals have a species-specific repertoire of affiliative behaviours that characterise individualised relationships within a group. To date, however, quantitative studies on intragroup affiliative behaviours in social carnivores have been limited. Here, we investigated the social functions of the two most commonly observed affiliative behaviours in captive African lions (Panthera leo: head rubbing and licking. We conducted behavioural observations on a captive group of lions composed of 7 males and 14 females, and tested hypotheses regarding three social functions: tension reduction, social bonding, and social status expression. Disproportionately frequent male-male and female-to-male head rubbing was observed, while more than 95% of all licking interactions occurred in female-female dyads. In accordance with the social bond hypothesis, and in disagreement with the social status expression hypothesis, both head rubbing and licking interactions were reciprocal. After controlling for spatial association, the dyadic frequency of head rubbing was negatively correlated with age difference while licking was positively correlated with relatedness. Group reunion after daily separation did not affect the frequencies of the affiliative behaviours, which was in disagreement with the predictions from the tension reduction hypothesis. These results support the social bond hypothesis for the functions of head rubbing and licking. Different patterns of affiliative behaviour between the sexes may reflect differences in the relationship quality in each sex or the differential predisposition to licking due to its original function in offspring care.

  18. Prostate cancer disparities in Black men of African descent: a comparative literature review of prostate cancer burden among Black men in the United States, Caribbean, United Kingdom, and West Africa

    Directory of Open Access Journals (Sweden)

    Reams R Renee

    2009-02-01

    Full Text Available Abstract Background African American men have the highest prostate cancer morbidity and mortality rates than any other racial or ethnic group in the US. Although the overall incidence of and mortality from prostate cancer has been declining in White men since 1991, the decline in African American men lags behind White men. Of particular concern is the growing literature on the disproportionate burden of prostate cancer among other Black men of West African ancestry in the Caribbean Islands, United Kingdom and West Africa. This higher incidence of prostate cancer observed in populations of African descent may be attributed to the fact that these populations share ancestral genetic factors. To better understand the burden of prostate cancer among men of West African Ancestry, we conducted a review of the literature on prostate cancer incidence, prevalence, and mortality in the countries connected by the Transatlantic Slave Trade. Results Several published studies indicate high prostate cancer burden in Nigeria and Ghana. There was no published literature for the countries Benin, Gambia and Senegal that met our review criteria. Prostate cancer morbidity and/or mortality data from the Caribbean Islands and the United Kingdom also provided comparable or worse prostate cancer burden to that of US Blacks. Conclusion The growing literature on the disproportionate burden of prostate cancer among other Black men of West African ancestry follows the path of the Transatlantic Slave Trade. To better understand and address the global prostate cancer disparities seen in Black men of West African ancestry, future studies should explore the genetic and environmental risk factors for prostate cancer among this group.

  19. Living Circumstances of Suicide Mortality in a South African City: An Ecological Study of Differences across Race Groups and Sexes

    Science.gov (United States)

    Burrows, Stephanie; Laflamme, Lucie

    2005-01-01

    In this study the importance of living area circumstances for suicide mortality was explored. Suicide mortality was assessed across race and sex groups in a South African city and the influence of area-based compositional and sociophysical characteristics on suicide risk was considered. Suicide mortality rates are highest among Whites, in…

  20. New World cattle show ancestry from multiple independent domestication events.

    Science.gov (United States)

    McTavish, Emily Jane; Decker, Jared E; Schnabel, Robert D; Taylor, Jeremy F; Hillis, David M

    2013-04-01

    Previous archeological and genetic research has shown that modern cattle breeds are descended from multiple independent domestication events of the wild aurochs (Bos primigenius) ∼10,000 y ago. Two primary areas of domestication in the Middle East/Europe and the Indian subcontinent resulted in taurine and indicine lines of cattle, respectively. American descendants of cattle brought by European explorers to the New World beginning in 1493 generally have been considered to belong to the taurine lineage. Our analyses of 47,506 single nucleotide polymorphisms show that these New World cattle breeds, as well as many related breeds of cattle in southern Europe, actually exhibit ancestry from both the taurine and indicine lineages. In this study, we show that, although European cattle are largely descended from the taurine lineage, gene flow from African cattle (partially of indicine origin) contributed substantial genomic components to both southern European cattle breeds and their New World descendants. New World cattle breeds, such as Texas Longhorns, provide an opportunity to study global population structure and domestication in cattle. Following their introduction into the Americas in the late 1400s, semiferal herds of cattle underwent between 80 and 200 generations of predominantly natural selection, as opposed to the human-mediated artificial selection of Old World breeding programs. Our analyses of global cattle breed population history show that the hybrid ancestry of New World breeds contributed genetic variation that likely facilitated the adaptation of these breeds to a novel environment. PMID:23530234

  1. Methodological Considerations in Estimation of Phenotype Heritability Using Genome-Wide SNP Data, Illustrated by an Analysis of the Heritability of Height in a Large Sample of African Ancestry Adults.

    Directory of Open Access Journals (Sweden)

    Fang Chen

    Full Text Available Height has an extremely polygenic pattern of inheritance. Genome-wide association studies (GWAS have revealed hundreds of common variants that are associated with human height at genome-wide levels of significance. However, only a small fraction of phenotypic variation can be explained by the aggregate of these common variants. In a large study of African-American men and women (n = 14,419, we genotyped and analyzed 966,578 autosomal SNPs across the entire genome using a linear mixed model variance components approach implemented in the program GCTA (Yang et al Nat Genet 2010, and estimated an additive heritability of 44.7% (se: 3.7% for this phenotype in a sample of evidently unrelated individuals. While this estimated value is similar to that given by Yang et al in their analyses, we remain concerned about two related issues: (1 whether in the complete absence of hidden relatedness, variance components methods have adequate power to estimate heritability when a very large number of SNPs are used in the analysis; and (2 whether estimation of heritability may be biased, in real studies, by low levels of residual hidden relatedness. We addressed the first question in a semi-analytic fashion by directly simulating the distribution of the score statistic for a test of zero heritability with and without low levels of relatedness. The second question was addressed by a very careful comparison of the behavior of estimated heritability for both observed (self-reported height and simulated phenotypes compared to imputation R2 as a function of the number of SNPs used in the analysis. These simulations help to address the important question about whether today's GWAS SNPs will remain useful for imputing causal variants that are discovered using very large sample sizes in future studies of height, or whether the causal variants themselves will need to be genotyped de novo in order to build a prediction model that ultimately captures a large fraction of the

  2. Challenges and opportunities for HIV prevention and care: insights from focus groups of HIV-infected African American men.

    Science.gov (United States)

    Buseh, Aaron G; Stevens, Patricia E; McManus, Patricia; Addison, Reverend Jim; Morgan, Sarah; Millon-Underwood, Sandra

    2006-01-01

    Given the inordinate burden of HIV illness borne by African American men, investigations of HIV prevention and care in this population are urgently needed. In this qualitative study, a sample of 20 HIV-infected African American men participated in two focus groups in which they exchanged experiences and ideas about living with HIV. They shared details about how they were personally impacted by HIV, and together they constructed a perspective on the larger societal context in which the HIV infection rate among African American men continues unabated. The men focused on growing complacency about HIV/AIDS in the United States, underfunding of supports and services, stigmas operative in African American communities, and differential care based on race, gender, and diagnosis. They saw opportunity in personal strategies that help individual men infected with HIV to take a more empowered stance to deal with the disease and improve their health but looked for changes undertaken by African Americans at the community level to make a real difference in the epidemic. Their vision included enhanced support for HIV prevention and care from influential community institutions like Black churches, more open dialogue about drugs and sexual behavior, and capacity-building for families whose members are HIV-infected or at risk for HIV. PMID:16849084

  3. Global divergence of the human follicle mite Demodex folliculorum: Persistent associations between host ancestry and mite lineages.

    Science.gov (United States)

    Palopoli, Michael F; Fergus, Daniel J; Minot, Samuel; Pei, Dorothy T; Simison, W Brian; Fernandez-Silva, Iria; Thoemmes, Megan S; Dunn, Robert R; Trautwein, Michelle

    2015-12-29

    Microscopic mites of the genus Demodex live within the hair follicles of mammals and are ubiquitous symbionts of humans, but little molecular work has been done to understand their genetic diversity or transmission. Here we sampled mite DNA from 70 human hosts of diverse geographic ancestries and analyzed 241 sequences from the mitochondrial genome of the species Demodex folliculorum. Phylogenetic analyses recovered multiple deep lineages including a globally distributed lineage common among hosts of European ancestry and three lineages that primarily include hosts of Asian, African, and Latin American ancestry. To a great extent, the ancestral geography of hosts predicted the lineages of mites found on them; 27% of the total molecular variance segregated according to the regional ancestries of hosts. We found that D. folliculorum populations are stable on an individual over the course of years and that some Asian and African American hosts maintain specific mite lineages over the course of years or generations outside their geographic region of birth or ancestry. D. folliculorum haplotypes were much more likely to be shared within families and between spouses than between unrelated individuals, indicating that transmission requires close contact. Dating analyses indicated that D. folliculorum origins may predate modern humans. Overall, D. folliculorum evolution reflects ancient human population divergences, is consistent with an out-of-Africa dispersal hypothesis, and presents an excellent model system for further understanding the history of human movement. PMID:26668374

  4. Genetic analysis of ancestry, admixture and selection in Bolivian and Totonac populations of the New World

    Directory of Open Access Journals (Sweden)

    Watkins W

    2012-05-01

    Full Text Available Abstract Background Populations of the Americas were founded by early migrants from Asia, and some have experienced recent genetic admixture. To better characterize the native and non-native ancestry components in populations from the Americas, we analyzed 815,377 autosomal SNPs, mitochondrial hypervariable segments I and II, and 36 Y-chromosome STRs from 24 Mesoamerican Totonacs and 23 South American Bolivians. Results and Conclusions We analyzed common genomic regions from native Bolivian and Totonac populations to identify 324 highly predictive Native American ancestry informative markers (AIMs. As few as 40–50 of these AIMs perform nearly as well as large panels of random genome-wide SNPs for predicting and estimating Native American ancestry and admixture levels. These AIMs have greater New World vs. Old World specificity than previous AIMs sets. We identify highly-divergent New World SNPs that coincide with high-frequency haplotypes found at similar frequencies in all populations examined, including the HGDP Pima, Maya, Colombian, Karitiana, and Surui American populations. Some of these regions are potential candidates for positive selection. European admixture in the Bolivian sample is approximately 12%, though individual estimates range from 0–48%. We estimate that the admixture occurred ~360–384 years ago. Little evidence of European or African admixture was found in Totonac individuals. Bolivians with pre-Columbian mtDNA and Y-chromosome haplogroups had 5–30% autosomal European ancestry, demonstrating the limitations of Y-chromosome and mtDNA haplogroups and the need for autosomal ancestry informative markers for assessing ancestry in admixed populations.

  5. A comprehensive examination of breast cancer risk loci in African American women

    OpenAIRE

    Feng, Ye; Stram, Daniel O.; Rhie, Suhn Kyong; Millikan, Robert C.; Ambrosone, Christine B.; John, Esther M; Bernstein, Leslie; Zheng, Wei; Olshan, Andrew F.; Jennifer J Hu; Ziegler, Regina G.; Nyante, Sarah; Bandera, Elisa V.; Sue A Ingles; Michael F. Press

    2014-01-01

    Genome-wide association studies have identified 73 breast cancer risk variants mainly in European populations. Given considerable differences in linkage disequilibrium structure between populations of European and African ancestry, the known risk variants may not be informative for risk in African ancestry populations. In a previous fine-mapping investigation of 19 breast cancer loci, we were able to identify SNPs in four regions that better captured risk associations in African American wome...

  6. End-Member modelling and quantification of terrigenous flux rates to the NW African continental margin during the late Pleistocene to Holocene

    Science.gov (United States)

    Just, Janna; von Dobeneck, Tilo; Bickert, Torsten; Frederichs, Thomas

    2010-05-01

    The region off Gambia is an interesting study area because of its geographical location in between the ITCZ summer and winter position. We study a sediment core spanning the last 60 kyrs off the Gambia river mouth (W Africa) to identify different sources of the terrigenous sediment components exported to the continental margin. Our aim is the quantification of terrigenous flux rates of fluvial and aeolian load, respectively to improve our understanding of palaeoclimatic conditions and climatic changes in the Sahel and Sahara. It is known that in western Africa arid conditions prevailed during glacials and North Atlantic Heinrich Events. After the Last Glacial Maximum (LGM) a humid climate dominated northern Africa between 5-12 kyrs BP, known as the African Humid Period (AHP). These climatic changes have already been documented in magnetic, chemical, mineralogical and sedimentological proxies, respectively. However, these investigations were mainly carried out in qualitative approaches and lack an integrated multi-proxy validation. We apply a multi-proxy approach using XRF-element data and environmental magnetic parameter analysis on 5 cm interval samples of sediment core GeoB13602-1 (13°32.71 N; 17°50.96 W). Carbonate and biogenic opal content were analysed to estimate the total terrigenous fraction. Environmental magnetic parameters including ARM, IRM, HIRM, SIRM and frequency-dependent susceptibility allow the estimation of magnetic minerals, e.g. magnetite, hematite and goethite. Ratios of these parameters reflect grainsizes of the magnetic minerals which are indicative of transport mechanisms. We performed an End-Member (EM) analysis of IRM acquisition curves, decomposing the bulk sample into different components which represent individual sediment sources. Our approach is to include chemical, sedimentological and magnetic parameters in this EM model to reconstruct the composition as well as the transport pathways of the sediments. Based on an age model

  7. Developing a guide for community-based groups to reduce alcohol-related harm among African migrants.

    Science.gov (United States)

    Jaworski, Alison; Brown, Tony; Norman, Catherine; Hata, Kiri; Toohey, Mark; Vasiljevic, Dubravka; Rowe, Rachel

    2016-04-01

    Issue addressed Alcohol-related harm is an issue of concern for African migrant communities living in Australia. However, there has been little information available to guide workers in developing culturally sensitive health promotion strategies. Methods A three-step approach, comprising a literature review, community consultations and an external review, was undertaken to develop a guide to assist organisations and health promotion groups working with African migrant communities to address alcohol-related harms. Discussion There was a high level of agreement between the three steps. Addressing alcohol harms with African migrant communities requires approaches that are sensitive to the needs, structures and experiences of communities. The process should incorporate targeted approaches that enable communities to achieve their resettlement goals as well as strengthening mainstream health promotion efforts. Conclusions The resource produced guides alcohol harm prevention coalitions and workers from the first steps of understanding the influences of acculturation and resettlement on alcohol consumption, through to planning, developing and evaluating an intervention in partnership with communities. So what? This paper advances knowledge by providing a precise summary of Australian African migrant focused alcohol and other drug research to date. It also describes a three-step approach that aimed to incorporate a diversity of community views in the creation of a health promotion and community capacity-building resource. PMID:26726816

  8. Aid & Trade: The European Union-African, Caribbean, & Pacific Group of States Framework within a Multi-Level Europe

    OpenAIRE

    Smith, Brent

    2009-01-01

    This project demonstrates how the European Union's aid and trade relationship with the African, Caribbean & Pacific (ACP) group of states fits within the context of a multi-level Europe. The analysis draws on the multi-level governance (MLG) typology designed by Liesbet Hooghe and Gary Marks, and the earlier intellectual endeavours of G.P.E. Walzenbach and colleagues to explain the EU governmental and policy process policies in aid and trade with ACP. By examining the nature and evolution...

  9. Crustal structure variations along the NW-African continental margin: a comparison of new and existing models from wide angle and reflection seismic data

    Science.gov (United States)

    Biari, Y.; Klingelhoefer, F.; Sahabi, M.; Aslanian, D.; Philippe, S.; Louden, K. E.; Berglar, K.; Moulin, M.; Mehdi, K.; Graindorge, D.; Evain, M.; Benabellouahed, M.; Reichert, C. J.

    2014-12-01

    Deep seismic data represent a key to understand the geometry and mechanism of continental rifting. The passive continental margin of NW-Africa is one of the oldest on earth, formed during the Upper Triassic-Lower Liassic rifting of the central Atlantic Ocean over 200 Ma. We present new and existing wide-angle and reflection seismic data from three study regions along the margin located in the North Moroccan salt basin, on the central continental margin offshore Safi and in the south, offshore Dakhla. In each of the study areas several combined wide-angle and reflection seismic profiles perpendicular and parallel to the margin have been acquired and forward modelled using comparable methods. The thickness of unthinned continental crust decreases from 36 km in the North to about 27 km in the South. In the North Moroccan Basin continental crust thins from originally 36 km to about 8 km in a 150 km wide zone. The basin itself is underlain by highly thinned continental crust. Offshore safi thinning of the continental crust is confined to a 130 km wide zone with no neighboring sedimentary basin underlain by continental crust. In both areas the zone of crustal thinning is characterised by the presence of large blocks and abundant salt diapirs. In the south crustal thinning is more rapid in a zone of 90 km and asymmetric with the upper crust thinning more closely to the continent than the lower crust, probably due to depth-dependent stretching and the presence of the precambrian Reguibat Ridge on land. Oceanic crust is characterised by a thickness of 7-8 km along the complete margin. Relatively high velocities of up to 7.5 km/s have been imaged between magnetic anomalies S1 and M25, and are probably related to changes in the spreading velocities at the time of the Kimmeridgian/Tithonian plate reorganisation. Volcanic activity seems to be confined to the region next to the Canary Islands, and is thus not related to the initial opening of the oceanic, which was related to no

  10. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  11. Geography and genography: prediction of continental origin using randomly selected single nucleotide polymorphisms

    Directory of Open Access Journals (Sweden)

    Ramoni Marco F

    2007-03-01

    Full Text Available Abstract Background Recent studies have shown that when individuals are grouped on the basis of genetic similarity, group membership corresponds closely to continental origin. There has been considerable debate about the implications of these findings in the context of larger debates about race and the extent of genetic variation between groups. Some have argued that clustering according to continental origin demonstrates the existence of significant genetic differences between groups and that these differences may have important implications for differences in health and disease. Others argue that clustering according to continental origin requires the use of large amounts of genetic data or specifically chosen markers and is indicative only of very subtle genetic differences that are unlikely to have biomedical significance. Results We used small numbers of randomly selected single nucleotide polymorphisms (SNPs from the International HapMap Project to train naïve Bayes classifiers for prediction of ancestral continent of origin. Predictive accuracy was tested on two independent data sets. Genetically similar groups should be difficult to distinguish, especially if only a small number of genetic markers are used. The genetic differences between continentally defined groups are sufficiently large that one can accurately predict ancestral continent of origin using only a minute, randomly selected fraction of the genetic variation present in the human genome. Genotype data from only 50 random SNPs was sufficient to predict ancestral continent of origin in our primary test data set with an average accuracy of 95%. Genetic variations informative about ancestry were common and widely distributed throughout the genome. Conclusion Accurate characterization of ancestry is possible using small numbers of randomly selected SNPs. The results presented here show how investigators conducting genetic association studies can use small numbers of arbitrarily

  12. Barriers and facilitators to participation in physical activity: The experiences of a group of South African adolescents with cerebral palsy.

    Science.gov (United States)

    Conchar, Lauren; Bantjes, Jason; Swartz, Leslie; Derman, Wayne

    2016-02-01

    Participation in regular physical activity promotes physical health and psychosocial well-being. Interventions are thus needed to promote physical activity, particularly among groups of individuals, such as persons with disability, who are marginalised from physical activity. This study explored the experiences of a group of South African adolescents with cerebral palsy. In-depth semi-structured interviews were conducted with 15 adolescents with cerebral palsy. The results provided insight into a range of factors that promote and hinder participation in physical activity among adolescents with cerebral palsy in resource-scarce environments. PMID:24607923

  13. Body Image and Quality of Life in a Group of African American Women

    Science.gov (United States)

    Cox, Tiffany L.; Zunker, Christie; Wingo, Brooks; Thomas, Dana-Marie; Ard, Jamy D.

    2010-01-01

    African American (AA) women's preference for a larger body size and underestimation of their body weight may affect the relationship between their body weight and weight-related quality of life (QOL). We wanted to examine the relationship between weight-related QOL and body mass index (BMI) in a sample of overweight AA women. Thirty-three…

  14. Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility

    OpenAIRE

    Mahajan, Anubha; Go, Min Jin; Zhang, Weihua; Below, Jennifer E.; Gaulton, Kyle J.; Ferreira, Teresa; Horikoshi, Momoko; Johnson, Andrew D.; Ng, Maggie C. Y.; Prokopenko, Inga; Saleheen, Danish; Wang, Xu; Zeggini, Eleftheria; Goncalo R. Abecasis; Adair, Linda S

    2014-01-01

    To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We observed a significant excess in the directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signal...

  15. Genome-wide Scan of 29,141 African Americans Finds No Evidence of Directional Selection since Admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W. Ryan

    2014-01-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection afte...

  16. Exploring psychosocial well-being in a group of marginalised African youth / S.R. Melato

    OpenAIRE

    Melato, Seleme Revelation

    2014-01-01

    This research using quantitative and qualitative methods studied the psychosocial well-being of marginalised youth of African descent in South Africa. The study of well-being amongst the youth has been the focus of many research studies in the past two decades (Bach, 2011; Koen, 2010; Ungar, 2005); hence the continuing intellectual debate on the best possible ways to promote youth well-being (Koen, 2010; Shah, Graidage, & Valencia, 2005; Van Schalkwyk, 2010). The major shift within the psycho...

  17. A group of black South Africans' experience of telling their untold stories about the apartheid era / Jacques Vermeulen

    OpenAIRE

    Vermeulen, Jacques

    2006-01-01

    The aim or this research was to explore a group of black South Africans' experiences of telling their untold stories of survival about the apartheid era. The expectation was that if they did become more aware of these alternative stories, it could have a far-reaching effect on their lives. Research indicates that when attention is given to these narratives they may be a powerful tool in not only recovering the story but also in focusing on the survivors' own consciousness and g...

  18. Information system agnostic ancestry for digital objects

    OpenAIRE

    Heuscher, S J B

    2010-01-01

    More and more information is becoming available in digital form, most of it derived from digital sources. Digital information is made available as digital objects composed of a sequence of bits and managed by information systems. To date, these digital objects have no independent identification which can be refered outside of a specific information system. However, they normally outlive these systems and can be copied to other systems. In order for the ancestry of digital information to span ...

  19. Blood Group Antigens C, Lub and P1 May Have a Role in HIV Infection in Africans.

    Directory of Open Access Journals (Sweden)

    Modisa Sekhamo Motswaledi

    Full Text Available Botswana is among the world's countries with the highest rates of HIV infection. It is not known whether or not this susceptibility to infection is due to genetic factors in the population. Accumulating evidence, however, points to the role of erythrocytes as potential mediators of infection. We therefore sought to establish the role, if any, of some erythrocyte antigens in HIV infection in a cross-section of the population.348 (346 HIV-negative and 2 HIV-positive samples were obtained from the National Blood Transfusion Service as residual samples, while 194 HIV-positive samples were obtained from the Botswana-Harvard HIV Reference Laboratory. Samples were grouped for twenty three antigens. Chi-square or Fischer Exact analyses were used to compare the frequencies of the antigens in the two groups. A stepwise, binary logistic regression was used to study the interaction of the various antigens in the light of HIV-status.The Rh antigens C and E were associated with HIV-negative status, while blood group Jka, P1 and Lub were associated with HIV-positive status. A stepwise binary logistic regression analysis yielded group C as the most significant protective blood group while Lub and P1 were associated with significantly higher odds ratio in favor of HIV-infection. The lower-risk-associated group C was significantly lower in Africans compared to published data for Caucasians and might partially explain the difference in susceptibility to HIV-1.The most influential antigen C, which also appears to be protective, is significantly lower in Africans than published data for Caucasians or Asians. On the other hand, there appear to be multiple antigens associated with increased risk that may override the protective role of C. A study of the distribution of these antigens in other populations may shed light on their roles in the HIV pandemic.

  20. Russia's Literary Genius Alexander Pushkin: The Great-Grandson of an African Slave.

    Science.gov (United States)

    Lounsbery, Anne

    2000-01-01

    Alexander Pushkin, Russia's most celebrated literary figure, descended from an African slave. On both parents' sides, he was related to Avram Petrovich Gannibal, who was born to an African prince and abducted to become a slave to a Russian diplomat. Pushkin chose to pride himself on both his aristocratic life and his African ancestry. (SM)

  1. Comparing genetic ancestry and self-reported race/ethnicity in a multiethnic population in New York City

    Indian Academy of Sciences (India)

    Yin Leng Lee; Susan Teitelbaum; Mary S. Wolff; James G. Wetmur; Jia Chen

    2010-12-01

    Self-reported race/ethnicity is frequently used in epidemiological studies to assess an individual’s background origin. However, in admixed populations such as Hispanic, self-reported race/ethnicity may not accurately represent them genetically because they are admixed with European, African and Native American ancestry. We estimated the proportions of genetic admixture in an ethnically diverse population of 396 mothers and 188 of their children with 35 ancestry informative markers (AIMs) using the STRUCTURE version 2.2 program. The majority of the markers showed significant deviation from Hardy–Weinberg equilibrium in our study population. In mothers self-identified as Black and White, the imputed ancestry proportions were 77.6% African and 75.1% European respectively, while the racial composition among self-identified Hispanics was 29.2% European, 26.0% African, and 44.8% Native American.We also investigated the utility of AIMs by showing the improved fitness of models in paraoxanase-1 genotype–phenotype associations after incorporating AIMs; however, the improvement was moderate at best. In summary, a minimal set of 35 AIMs is sufficient to detect population stratification and estimate the proportion of individual genetic admixture; however, the utility of these markers remains questionable.

  2. Ancestry informative markers and complete blood count parameters in Brazilian blood donors

    Directory of Open Access Journals (Sweden)

    Gabriela E. S. Felix

    2010-01-01

    Full Text Available A complete blood count is very useful in clinical diagnoses when reference ranges are well established for the population. Complete blood counts and allele frequencies of Ancestry Informative Markers (AIMs were analyzed in Brazilians with the aim of characterizing the hematological values of an admixed population. Positive associations were observed between gender and neutrophils, monocytes, eosinophils, erythrocytes, hemoglobin, hematocrit, MCV, MCHC and platelet counts. No significant differences were found for age, alcohol consumption, educational status, ethnicity, smoking in respect to the complete blood count values. In general, men had higher red blood cell values, while women had higher values for white blood cells and platelets. The study of the population was highly heterogeneous with mean proportions (± SE of African, European and Amerindian ancestry being 49.0 ± 3.0%, 44.0 ± 9.0% and 7.0 ± 9.0%, respectively. Amerindian ancestry showed limited contribution to the makeup of the population, but estimated ancestral proportions were statistically significant (r = 0.9838; P<0.001. These hematologic values are similar to Afro-Americans, another admixed population.

  3. Assessing the reliability of eBURST using simulated populations with known ancestry

    OpenAIRE

    Connor Thomas R; Fraser Christophe; Hanage William P; Turner Katherine ME; Spratt Brian G

    2007-01-01

    Abstract Background The program eBURST uses multilocus sequence typing data to divide bacterial populations into groups of closely related strains (clonal complexes), predicts the founding genotype of each group, and displays the patterns of recent evolutionary descent of all other strains in the group from the founder. The reliability of eBURST was evaluated using populations simulated with different levels of recombination in which the ancestry of all strains was known. Results For strictly...

  4. Maximum-likelihood estimation of recent shared ancestry (ERSA)

    OpenAIRE

    Huff, Chad D.; Witherspoon, David J.; Simonson, Tatum S.; Xing, Jinchuan; Watkins, W Scott; Zhang, Yuhua; Tuohy, Therese M; Neklason, Deborah W.; Burt, Randall W.; Guthery, Stephen L; Woodward, Scott R.; Jorde, Lynn B

    2011-01-01

    Accurate estimation of recent shared ancestry is important for genetics, evolution, medicine, conservation biology, and forensics. Established methods estimate kinship accurately for first-degree through third-degree relatives. We demonstrate that chromosomal segments shared by two individuals due to identity by descent (IBD) provide much additional information about shared ancestry. We developed a maximum-likelihood method for the estimation of recent shared ancestry (ERSA) from the number a...

  5. African Geography for Schools: A Handbook for Teachers. A Unesco Source Book.

    Science.gov (United States)

    Brouillette, B., Ed.; And Others

    This book is the first in a series of UNESCO guide books for teaching geography on a continental scale, dealing with either land masses or vast regional groups which have common characteristics. Written by African geographers, it is intended for primary and secondary school teachers, teacher-training institutions in Africa, and also for geography…

  6. Continental drilling

    Energy Technology Data Exchange (ETDEWEB)

    Shoemaker, E.M. (ed.)

    1975-01-01

    The Workshop on Continental Drilling was convened to prepare a report for submission to the US Geodynamics Committee with respect to the contribution that could be made by land drilling to resolve major problems of geodynamics and consider the mechanisms by which the responsibility for scientific planning, establishment of priorities, administration, and budgeting for a land-drilling program within the framework of the aims of the Geodynamics Project would best be established. A new and extensive program to study the continental crust is outlined in this report. The Workshop focused on the following topics: processes in the continental crust (mechanism of faulting and earthquakes, hydrothermal systems and active magma chambers); state and structure of the continental crust (heat flow and thermal structure of the crust; state of ambient stress in the North American plate; extent, regional structure, and evolution of crystalline continental crust); short hole investigations; present state and needs of drilling technology; drill hole experimentation and instrumentation; suggestions for organization and operation of drilling project; and suggested level of effort and funding. Four recommendations are set down. 8 figures, 5 tables. (RWR)

  7. What the Face and Body Reveal: In-Group Emotion Effects and Stereotyping of Emotion in African American and European American Children

    Science.gov (United States)

    Tuminello, Elizabeth R.; Davidson, Denise

    2011-01-01

    This study examined whether 3- to 7-year-old African American and European American children's assessment of emotion in face-only, face + body, and body-only photographic stimuli was affected by in-group emotion recognition effects and racial or gender stereotyping of emotion. Evidence for racial in-group effects was found, with European American…

  8. "The bullets sound like music to my ears" : socialization of child soldiers within African rebel groups

    NARCIS (Netherlands)

    Vermeij, L.

    2014-01-01

    Based on over 400 in-depth interviews with child soldiers and their commanders, this research reveals how rebel group socialization leads to allegiance among child soldiers and how this contributes to the creation of a cohesive group.

  9. Forming Representative Household and Factor Groups for a South African SAM

    OpenAIRE

    Pauw, Kalie

    2005-01-01

    This Technical Paper explains the formation of representative households and factor groups for inclusion in the PROVIDE Project Social Accounting Matrix. A general guideline for forming household and/or factor groups is that they should reproduce the socio-economic stratification within the society as accurately as possible. Such groups should also be made up of 'relatively homogenous' groups that are easily recognisable for policy purposes. Here the Income and Expenditure Survey (2000) and L...

  10. Environmental conditions associated with repetitive behavior in a group of African elephants.

    Science.gov (United States)

    Hasenjager, Matthew J; Bergl, Richard A

    2015-01-01

    Repetitive movement patterns are commonly observed in zoo elephants. The extent to which these behaviors constitute a welfare concern varies, as their expression ranges from stereotypies to potentially beneficial anticipatory behaviors. Nevertheless, their occurrence in zoo animals is often viewed negatively. To better identify conditions that prompt their performance, observations were conducted on six African elephants (Loxodonta africana) at the North Carolina Zoo. Individuals spent most of their time engaged in feeding, locomotion, resting, and repetitive behavior. Both generalized estimating equation and zero-inflated negative binomial models were used to identify factors associated with increased rates of repetitive behavior. Time of day in conjunction with location on- or off-exhibit best explained patterns of repetitive behavior. Repetitive behaviors occurred at a lower rate in the morning when on-exhibit, as compared to afternoons on-exhibit or at any time of day off-exhibit. Increased repetitive behavior rates observed on-exhibit in the afternoon prior to the evening transfer and feeding were possibly anticipatory responses towards those events. In contrast, consistently elevated frequencies of repetitive behavior off-exhibit at all times of day could be related to differences in exhibit complexity between off-exhibit and on-exhibit areas, as well as a lack of additional foraging opportunities. Our study contributes valuable information on captive elephant behavior and represents a good example of how behavioral research can be employed to improve management of zoo animals. PMID:25919392

  11. Continental tectonics and continental kinetics

    International Nuclear Information System (INIS)

    We present a model of continental growth which combines the results of geochemical studies and tectonic ideas about the evolution of continents through geological time. The process of continental growth is mainly controlled by surface phenomena. Continental material is extracted from the mantle along subduction zones at the periphery of oceans, and is destroyed in collision zones where it is remobilized and made available for subduction. We derive an equation for S, the portion of the Earth's surface occupied by continents, which reads as follows: dS/dt=a . √(1-S)-b . S. Coefficients a and b depend on the geometry of plates, on their number and on their velocities. We assume that they decrease exponentially with time with the same time-scale α. This model satisfies both geochemical and tectonic constraints, and allows the integration of several current observations in a single framework. (orig.)

  12. Typing of 111 ancestry informative markers in an Albanian population

    DEFF Research Database (Denmark)

    Ribeiro, Joana; Pereira, V.; Kondili, A.; Miniati, P.; Børsting, C.; Morling, N.

    2015-01-01

    Genetically based prediction of ancestry has a great potential in forensic genetics and may be used as an investigative lead in crime case work or missing person identification.The EUROFORGEN-NoE consortium developed four PCR and SBE multiplexes for typing of 111 ancestry informative markers (AIM...

  13. Trophic Groups Of Demersal Fish Of Santos Bay And Adjacent Continental Shelf, São Paulo State, Brazil: Temporal And Spatial Comparisons

    Directory of Open Access Journals (Sweden)

    Elizabeti Y. Muto

    2014-07-01

    Full Text Available The temporal and spatial variations of feeding habits and trophic groups of demersal fish species of Santos Bay and the adjacent continental shelf were investigated. The samples were taken in September 2005 and March 2006 by bottom otter trawling. The stomach content analysis of 2,328 specimens of 49 species showed most fish fed on a large range of food items but relied heavily on shrimp, crabs/swimming-crabs, amphipods, mysids, polychaetes, ophiuroids, squids, and teleosteans. The species were classified into ten trophic groups. Shrimp were an important food source in the Santos bay and inner shelf, while ophiuroids were important prey for predators of the middle shelf. Many species relied on crabs/swimming-crabs during the summer, especially on the middle shelf. The spatial and temporal variability in food resource utilization by fish were related to the pattern of distribution and abundance of their prey. The predation on shrimp and crabs/swimming-crabs seems to be related to the water mass dynamics of the region. Intraspecific comparisons demonstrated that most of the species display spatial and/or temporal variation in their diet. The demersal ichtyofauna can also be divided into the more general categories of piscivores, nektonic invertebrate feeders, benthic invertebrate feeders and planktonic invertebrate feeders.

  14. Analysis of pharmacogenetic traits in two distinct South African populations

    Directory of Open Access Journals (Sweden)

    Ikediobi Ogechi

    2011-05-01

    Full Text Available Abstract Our knowledge of pharmacogenetic variability in diverse populations is scarce, especially in sub-Saharan Africa. To bridge this gap in knowledge, we characterised population frequencies of clinically relevant pharmacogenetic traits in two distinct South African population groups. We genotyped 211 tagging single nucleotide polymorphisms (tagSNPs in 12 genes that influence antiretroviral drug disposition, in 176 South African individuals belonging to two distinct population groups residing in the Western Cape: the Xhosa (n = 109 and Cape Mixed Ancestry (CMA (n = 67 groups. The minor allele frequencies (MAFs of eight tagSNPs in six genes (those encoding the ATP binding cassette sub-family B, member 1 [ABCB1], four members of the cytochrome P450 family [CYP2A7P1, CYP2C18, CYP3A4, CYP3A5] and UDP-glucuronosyltransferase 1 [UGT1A1] were significantly different between the Xhosa and CMA populations (Bonferroni p CYP2C18, CYP3A4, the gene encoding solute carrier family 22 member 6 [SLC22A6] and UGT1A1 between the two South African populations. Characterising the Xhosa and CMA population frequencies of variant alleles important for drug transport and metabolism can help to establish the clinical relevance of pharmacogenetic testing in these populations.

  15. Association of genetic ancestry with breast cancer in ethnically diverse women from Chicago.

    Directory of Open Access Journals (Sweden)

    Umaima Al-Alem

    Full Text Available INTRODUCTION: Non-Hispanic (nH Black and Hispanic women are disproportionately affected by early onset disease, later stage, and with more aggressive, higher grade and ER/PR negative breast cancers. The purpose of this analysis was to examine whether genetic ancestry could account for these variation in breast cancer characteristics, once data were stratified by self-reported race/ethnicity and adjusted for potential confounding by social and behavioral factors. METHODS: We used a panel of 100 ancestry informative markers (AIMs to estimate individual genetic ancestry in 656 women from the "Breast Cancer Care in Chicago" study, a multi-ethnic cohort of breast cancer patients to examine the association between individual genetic ancestry and breast cancer characteristics. In addition we examined the association of individual AIMs and breast cancer to identify genes/regions that may potentially play a role in breast cancer disease disparities. RESULTS: As expected, nH Black and Hispanic patients were more likely than nH White patients to be diagnosed at later stages, with higher grade, and with ER/PR negative tumors. Higher European genetic ancestry was protective against later stage at diagnosis (OR 0.7 95%CI: 0.54-0.92 among Hispanic patients, and higher grade (OR 0.73, 95%CI: 0.56-0.95 among nH Black patients. After adjustment for multiple social and behavioral risk factors, the association with later stage remained, while the association with grade was not significant. We also found that the AIM SNP rs10954631 on chromosome 7 was associated with later stage (p = 0.02 and higher grade (p = 0.012 in nH Whites and later stage (p = 0.03 in nH Blacks. CONCLUSION: Non-European genetic ancestry was associated with later stage at diagnosis in ethnic minorities. The relation between genetic ancestry and stage at diagnosis may be due to genetic factors and/or unmeasured environmental factors that are overrepresented within certain racial

  16. Worldwide Estimates Relative to Five Continental-Scale Populations

    OpenAIRE

    Steele, Christopher D.; Court, Denise Syndercombe; Balding, David J.

    2014-01-01

    We estimate the population genetics parameter (also referred to as the fixation index) from short tandem repeat (STR) allele frequencies, comparing many worldwide human subpopulations at approximately the national level with continental-scale populations. is commonly used to measure population differentiation, and is important in forensic DNA analysis to account for remote shared ancestry between a suspect and an alternative source of the DNA. We estimate comparing subpopulations with a hypot...

  17. Group Interventions with Low-Income African American Women Recovering from Chemical Dependency.

    Science.gov (United States)

    Washington, Olivia G. M.; Moxley, David P.

    2003-01-01

    Presents finding from an investigation of two group therapy modalities involving 93 women with dependent children and limited education and income levels. An overview of intervention activities that participants found beneficial is presented. Programs were found to help participants develop a sense of community, reduce stress, improve…

  18. The South African Personality Inventory (SAPI): a culture-informed instrument for the country's main ethnocultural groups.

    Science.gov (United States)

    Fetvadjiev, Velichko H; Meiring, Deon; van de Vijver, Fons J R; Nel, J Alewyn; Hill, Carin

    2015-09-01

    We present the development and the underlying structure of a personality inventory for the main ethnocultural groups of South Africa, using an emic-etic approach. The South African Personality Inventory (SAPI) was developed based on an extensive qualitative study of the implicit personality conceptions in the country's 11 official languages (Nel et al., 2012). Items were generated and selected (to a final set of 146) with a continuous focus on cultural adequacy and translatability. Students and community adults (671 Blacks, 198 Coloreds, 104 Indians, and 391 Whites) completed the inventory. A 6-dimensional structure (comprising a positive and a negative Social-Relational factor, Neuroticism, Extraversion, Conscientiousness, and Openness) was equivalent across groups and replicated in an independent sample of 139 Black and 270 White students. The SAPI correlated highly overall with impression-management aspects, but lower with lying aspects of social desirability. The SAPI social-relational factors were distinguishable from the Big Five in a joint factor analysis; the multiple correlations with the Big Five were .64 (positive) and .51 (negative social-relational). Implications and suggestions for emic-etic instrument and model development are discussed. PMID:25602691

  19. The ability of health promoters to deliver group diabetes education in South African primary care

    Directory of Open Access Journals (Sweden)

    Anna S. Botes

    2013-01-01

    Full Text Available Background: Diabetes makes a significant contribution to the burden of disease in South Africa.This study assesses a group diabetes education programme using motivational interviewingin public sector health centres serving low socio-economic communities in Cape Town.The programme was delivered by mid-level health promotion officers (HPOs.Objectives: The aim of the study was to explore the experience of the HPOs and to observetheir fidelity to the educational programme.Methods: Three focus group interviews were held with the 14 HPOs who delivered theeducational programme in 17 health centres. Thirty-three sessions were observed directly andthe audio tapes were analysed using the motivational interviewing (MI integrity code.Results: The HPOs felt confident in their ability to deliver group education after receiving thetraining. They reported a significant shift in their communication style and skills. They feltthe new approach was feasible and better than before. The resource material was found to berelevant, understandable and useful. The HPOs struggled with poor patient attendance and alack of suitable space at the facilities. They delivered the majority of the content and achievedbeginning-level proficiency in the MI guiding style of communication and the use of openquestions. The HPOs did not demonstrate proficiency in active listening and continued to offersome unsolicited advice.Conclusion: The HPOs demonstrated their potential to deliver group diabetes education despiteissues that should be addressed in future training and the district health services. Thefindings will help with the interpretation of results from a randomised controlled trial evaluatingthe effectiveness of the education.

  20. HIV/AIDS through the lens of Christianity: perspectives from a South African urban support group.

    Science.gov (United States)

    Hlongwana, K; Mkhize, S

    2007-05-01

    HIV is one of the most obscure viruses that humankind has had to face in recent times. Compounding this obscurity are often contesting perspectives on what it means to be HIV infected, and these perspectives are largely constituted by people's rationalisation of complex situations or experiences. Using qualitative research methods and ethnography in particular, this paper reflects on a broad understanding of what it means to live with HIV in the context of Christianity, using research participants' perspectives in an urban support group setting. Two fundamental patterns are evident in this paper: (1) as support group members rationalise their HIV infection, they continuously construct and reconstruct their identities; and (2) support group members rationalise their HIV infection to enhance their coping abilities, using Christianity and the Bible in particular, as a reference. Whilst rationalising HIV infection, three viewpoints emerge. The first viewpoint perceives HIV infection as an affliction by Satan; the second viewpoint sees it as originating from God; while the last viewpoint interprets HIV infection as a negotiated settlement between God and Satan. The paper is intended to trigger debate, and hopefully also to seek and provide answers from various sectors of society, and religious communities in particular, in order to help other HIV positive people in similar situations better manage their HIV condition. PMID:18040534

  1. Energy and Macronutrients Intake in Two Age Groups of Black South African Women

    Directory of Open Access Journals (Sweden)

    O.O. Oguntibeju

    2008-01-01

    Full Text Available The transition to a more westernized diets, became evident in the macronutrient intake of women in this study. The consumption of an energy-dense and diverse diet, typical of this transition, contributed to the high mean total energy and protein intakes. High mean total carbohydrate intakes, a staple diet of cereals and grains was also reported. The adequate intake of dietary fibre by the population group in this study was in contrast with international studies that reported that westernization leads to increased consumption of fibre-depleted carbohydrates. The high total fat intake observed in this study may be ascribed to the increasing preference for cheaper red meat, offal, eggs, full-cream milk, cheese, brick margarine and meat drippings used in food preparation. The inclusion of these foods in the diet could explain the high total cholesterol intake reported in this study. Although the food trends of the studied group of women tended to move towards a more westernized style, traditional foods have not been totally eliminated. It is thus clear that urbanisation in this study group has led to high consumption rates of carbonated drinks, cold drinks, coffee, tea and commercial beer. A cereal-based diet was still taken; unfortunately, many of these foods were consumed in the refined form.

  2. Continental dynamics and continental earthquakes

    Institute of Scientific and Technical Information of China (English)

    张东宁; 张国民; 张培震

    2003-01-01

    Two key research projects in geoscience field in China since the IUGG meeting in Birmingham in 1999, the project of "East Asian Continental Geodynamics" and the project of "Mechanism and Prediction of Strong Continental Earthquakes" are introduced in this paper. Some details of two projects, such as their sub-projects, some initial research results published are also given here. Because of the large magnitude of the November 14, 2001 Kunlun Mountain Pass MS=8.1 earthquake, in the third part of this paper, some initial research results are reviewed for the after-shock monitoring and the multi-discipline field survey, the impact and disaster of this earthquake on the construction site of Qinghai-Xizang (Tibet) railway and some other infrastructure.

  3. A zymodeme study of Entamoeba histolytica in a group of South African schoolchildren.

    Science.gov (United States)

    Sargeaunt, P G; Williams, J E; Jackson, T F; Simjee, A E

    1982-01-01

    Using a biphasic culture medium, stocks of intestinal amoebae were isolated from a group of children attending school in Durban, South Africa. These were compared with stocks collected in other areas of the world already characterized using the electrophoretic patterns of four enzymes: glucose phosphate isomerase (GPI), phosphoglucomutase (PGM) L-malate: NADP+ oxido-reductase (oxalacetate-decarboxylating) (ME) and hexokinase (HK). 33% of 94 samples grew Entamoeba histolytica, only one of which gave a pattern indicative of a pathogenic stock. Entamoeba hartmanni, Dientamoeba fragilis and Entamoeba coli were also grown from some samples, increasing the total positive samples for all species isolated to 40%. PMID:6287686

  4. Untold Stories of a group of Black South Africans about the Apartheid Era

    OpenAIRE

    Venter, Christiaan; E.J. van der Merwe; Temane, Qambeshile

    2009-01-01

    The aim of this research was to explore the alternative stories of a group of black adults who survived the apartheid years in South Africa. In common parlance it is held that there are two sides to a story and surely, there must have been alternative stories of how people in the black community survived the apartheid years, other than only the dominant stories of suffering that came to the fore during the Truth and Reconciliation Commission (TRC) hearings. It was surmised that the lives of m...

  5. Electron microprobe chemical ages of monazite from Qinling Group in the Qinling Orogen:Evidence for Late Pan-African metamorphism?

    Institute of Scientific and Technical Information of China (English)

    CHEN Qiang; CHEN Nengsong; WANG Qinyan; SUN Min; WANG Xinyu; LI Xiaoyan; SHU Guiming

    2006-01-01

    Electron microprobe chemical dating was carried out on monazites enclosed in two generations of mineral paragenesis of St + Ky + Grt and Sil + And + Grt + St, respectively, from the Qinling Group. Two different ages, 520±23 Ma and 435±9 Ma,were obtained from these monazites. This indicates that the Qinling Group experienced a metamorphism during the Early Cambrian, which is probably in response to the Late Pan-African subduction-accretion tectonothermal event.

  6. Environmental influences on African migration to Canada: focus group findings from Ottawa-Gatineau.

    Science.gov (United States)

    Veronis, Luisa; McLeman, Robert

    2014-01-01

    There is limited empirical evidence of how environmental conditions in the Global South may influence long-distance international migration to the Global North. This research note reports findings from seven focus groups held in Ottawa-Gatineau, Canada, with recent migrants from the Horn of Africa and francophone sub-Saharan Africa, where the role of environment in migration decision-making was discussed. Participants stated that those most affected by environmental challenges in their home countries lack the financial wherewithal to migrate to Canada. Participants also suggested that internal rural-urban migration patterns generated by environmental challenges in their home countries underlay socioeconomic factors that contributed to their own migration. In other words, environment is a second- or third-order contributor in a complex chain of interactions in the migrant source country that may lead to long-distance international migration by skilled and educated urbanites. These findings have informed the scope and detail of a larger, ongoing empirical study of environmental influences on immigration to Canada. PMID:25400310

  7. Voice and handgrip strength predict reproductive success in a group of indigenous African females.

    Directory of Open Access Journals (Sweden)

    Jeremy Atkinson

    Full Text Available Evolutionary accounts of human traits are often based on proxies for genetic fitness (e.g., number of sex partners, facial attractiveness. Instead of using proxies, actual differences in reproductive success is a more direct measure of darwinian fitness. Certain voice acoustics such as fundamental frequency and measures of health such as handgrip strength correlate with proxies of fitness, yet there are few studies showing the relation of these traits to reproduction. Here, we explore whether the fundamental frequency of the voice and handgrip strength account for differences in actual reproduction among a population of natural fertility humans. Our results show that both fundamental frequency and handgrip strength predict several measures of reproductive success among a group of indigenous Namibian females, particularly amongst the elderly, with weight also predicting reproductive outcomes among males. These findings demonstrate that both hormonally regulated and phenotypic quality markers can be used as measures of darwinian fitness among humans living under conditions that resemble the evolutionary environment of Homo sapiens. We also argue that these findings provide support for the Grandmother Hypothesis.

  8. Frequencies of HID-ion ampliseq ancestry panel markers among greenlanders.

    Science.gov (United States)

    Espregueira Themudo, Gonçalo; Smidt Mogensen, Helle; Børsting, Claus; Morling, Niels

    2016-09-01

    The HID-Ion AmpliSeq Ancestry Panel from Life Techologies includes 123 SNPs from the Seldin panel and 55 SNPs from Kidd panel in a single multiplex assay that helps to determine the continental biogeographic ancestry of individuals. We tested the panel on 104 Greenlanders, divided into a training set of 89 individuals and a test set of 15 individuals. All loci showed genotype distributions consistent with Hardy-Weinberg expectations. Linkage disequilibrium tests indicated that 14 pairs of loci were in association in Greenlanders. Population assignment of the training set to populations included in the HID SNP genotyper plugin placed most individuals in American, Asian, and in a few cases European populations. By including the genotype frequencies of this training set as a possible population of origin, all 15 individuals from the test set were correctly predicted to be Greenlanders using the Seldin SNPs, and nine were classified as Greenlanders using the Kidd SNPs. Population structure analysis indicated that Greenlanders have a genetic profile that is distinguishable from those of populations from America or Asia. PMID:27326551

  9. Burden of invasive group B Streptococcus disease and early neurological sequelae in South African infants.

    Directory of Open Access Journals (Sweden)

    Ziyaad Dangor

    Full Text Available Group B Streptococcus (GBS is a leading cause of neonatal sepsis and meningitis. We aimed to evaluate the burden of invasive early-onset (0-6 days of life, EOD and late-onset (7-89 days, LOD GBS disease and subsequent neurological sequelae in infants from a setting with a high prevalence (29.5% of HIV among pregnant women.A case-control study was undertaken at three secondary-tertiary care public hospitals in Johannesburg. Invasive cases in infants <3 months age were identified by surveillance of laboratories from November 2012 to February 2014. Neurodevelopmental screening was done in surviving cases and controls at 3 and 6 months of age.We identified 122 cases of invasive GBS disease over a 12 month period. Although the incidence (per 1,000 live births of EOD was similar between HIV-exposed and HIV-unexposed infants (1.13 vs. 1.46; p = 0.487, there was a 4.67-fold (95%CI: 2.24-9.74 greater risk for LOD in HIV-exposed infants (2.27 vs. 0.49; p<0.001. Overall, serotypes Ia, Ib and III constituted 75.8% and 92.5% of EOD and LOD, respectively. Risk factors for EOD included offensive draining liquor (adjusted Odds Ratio: 27.37; 95%CI: 1.94-386.50 and maternal GBS bacteriuria (aOR: 8.41; 95%CI: 1.44-49.15, which was also a risk-factor for LOD (aOR: 3.49; 95%CI: 1.17-10.40. The overall case fatality rate among cases was 18.0%. The adjusted odds for neurological sequelae at 6 months age was 13.18-fold (95%CI: 1.44-120.95 greater in cases (13.2% than controls (0.4%.The high burden of invasive GBS disease in South Africa, which is also associated with high case fatality rates and significant neurological sequelae among survivors, is partly due to the heightened risk for LOD in infants born to HIV-infected women. An effective trivalent GBS conjugate vaccine targeted at pregnant women could prevent invasive GBS disease in this setting.

  10. Disparities in Birth Weight and Gestational Age by Ethnic Ancestry in South American countries

    Science.gov (United States)

    Wehby, George L.; Gili, Juan A.; Pawluk, Mariela; Castilla, Eduardo E.; López-Camelo, Jorge S.

    2015-01-01

    Objective We examine disparities in birth weight and gestational age by ethnic ancestry in 2000–2011 in eight South American countries. Methods The sample included 60480 singleton live-births. Regression models were estimated to evaluate differences in birth outcomes by ethnic ancestry controlling for time trends. Results Significant disparities were found in seven countries. In four countries – Brazil, Ecuador, Uruguay, and Venezuela – we found significant disparities in both low birth weight and preterm birth. Disparities in preterm birth alone were observed in Argentina, Bolivia, and Colombia. Several differences in continuous birth weight, gestational age, and fetal growth rate were also observed. There were no systematic patterns of disparities between the evaluated ethnic ancestry groups across the study countries, in that no racial/ethnic group consistently had the best or worst outcomes in all countries. Conclusions Racial/ethnic disparities in infant health are common in several South American countries. Differences across countries suggest that racial/ethnic disparities are driven by social and economic mechanisms. Researchers and policymakers should acknowledge these disparities and develop research and policy programs to effectively target them. PMID:25542227

  11. Multiple origins and regional dispersal of resistant dhps in African Plasmodium falciparum malaria.

    Directory of Open Access Journals (Sweden)

    Richard J Pearce

    2009-04-01

    Full Text Available BACKGROUND: Although the molecular basis of resistance to a number of common antimalarial drugs is well known, a geographic description of the emergence and dispersal of resistance mutations across Africa has not been attempted. To that end we have characterised the evolutionary origins of antifolate resistance mutations in the dihydropteroate synthase (dhps gene and mapped their contemporary distribution. METHODS AND FINDINGS: We used microsatellite polymorphism flanking the dhps gene to determine which resistance alleles shared common ancestry and found five major lineages each of which had a unique geographical distribution. The extent to which allelic lineages were shared among 20 African Plasmodium falciparum populations revealed five major geographical groupings. Resistance lineages were common to all sites within these regions. The most marked differentiation was between east and west African P. falciparum, in which resistance alleles were not only of different ancestry but also carried different resistance mutations. CONCLUSIONS: Resistant dhps has emerged independently in multiple sites in Africa during the past 10-20 years. Our data show the molecular basis of resistance differs between east and west Africa, which is likely to translate into differing antifolate sensitivity. We have also demonstrated that the dispersal patterns of resistance lineages give unique insights into recent parasite migration patterns.

  12. Disparity in the Persistence of High-Risk Human Papillomavirus Genotypes Between African American and European American Women of College Age

    OpenAIRE

    Banister, Carolyn E.; Messersmith, Amy R.; Cai, Bo; Spiryda, Lisa B; Glover, Saundra H.; Pirisi, Lucia; Creek, Kim E

    2014-01-01

    Background. Cervical cancer incidence and mortality rates are higher in African Americans than in European Americans (white, non-Hispanic of European ancestry). The reasons for this disparity are not known.

  13. Continental Rifts

    Science.gov (United States)

    Rosendahl, B. R.

    Continental Rifts, edited by A. M. Quennell, is a new member of the Benchmark Papers in Geology Series, edited in toto by R. W. Fairbridge. In this series the individual volume editors peruse the literature on a given topic, select a few dozen papers of ostensibly benchmark quality, and then reorder them in some sensible fashion. Some of the original papers are republished intact, but many are chopped into “McNuggets™” of information. Depending upon the volume editor, the chopping process can range from a butchering job to careful and prudent pruning. The collecting, sifting, and reorganizing tasks are, of course, equally editor-sensitive. The end product of this series is something akin to a set of Reader's Digest of Geology.

  14. Forensic ancestry analysis with two capillary electrophoresis ancestry informative marker (AIM) panels:Results of a collaborative EDNAP exercise

    OpenAIRE

    Santos, C.; Fondevila, M; Ballard, D; Banemann, R; Bento, A. M.; Børsting, C; Branicki, W.; Brisighelli, F.; Burrington, M.; Capal, T.; Chaitanya, L; Daniel, R; Decroyer, V.; R. England; Gettings, K. B.

    2015-01-01

    There is increasing interest in forensic ancestry tests, which are part of a growing number of DNA analyses that can enhance routine profiling by obtaining additional genetic information about unidentified DNA donors. Nearly all ancestry tests use single nucleotide polymorphisms (SNPs), but these currently rely on SNaPshot single base extension chemistry that can fail to detect mixed DNA. Insertion-deletion polymorphism (Indel) tests have been developed using dye-labeled primers that allow di...

  15. Genetic ancestry of the extinct Javan and Bali tigers.

    Science.gov (United States)

    Xue, Hao-Ran; Yamaguchi, Nobuyuki; Driscoll, Carlos A; Han, Yu; Bar-Gal, Gila Kahila; Zhuang, Yan; Mazak, Ji H; Macdonald, David W; O'Brien, Stephen J; Luo, Shu-Jin

    2015-01-01

    The Bali (Panthera tigris balica) and Javan (P. t. sondaica) tigers are recognized as distinct tiger subspecies that went extinct in the 1940s and 1980s, respectively. Yet their genetic ancestry and taxonomic status remain controversial. Following ancient DNA procedures, we generated concatenated 1750bp mtDNA sequences from 23 museum samples including 11 voucher specimens from Java and Bali and compared these to diagnostic mtDNA sequences from 122 specimens of living tiger subspecies and the extinct Caspian tiger. The results revealed a close genetic affinity of the 3 groups from the Sunda Islands (Bali, Javan, and Sumatran tigers P. t. sumatrae). Bali and Javan mtDNA haplotypes differ from Sumatran haplotypes by 1-2 nucleotides, and the 3 island populations define a monophyletic assemblage distinctive and equidistant from other mainland subspecies. Despite this close phylogenetic relationship, no mtDNA haplotype was shared between Sumatran and Javan/Bali tigers, indicating little or no matrilineal gene flow among the islands after they were colonized. The close phylogenetic relationship among Sunda tiger subspecies suggests either recent colonization across the islands, or else a once continuous tiger population that had subsequently isolated into different island subspecies. This supports the hypothesis that the Sumatran tiger is the closest living relative to the extinct Javan and Bali tigers. PMID:25754539

  16. Meta-analysis of loci associated with age at natural menopause in African-American women

    OpenAIRE

    Chen, Christina T. L.; Liu, Ching-Ti; Chen, Gary K.; Andrews, Jeanette S.; Arnold, Alice M.; Dreyfus, Jill; Franceschini, Nora; Garcia, Melissa E.; Kerr, Kathleen F.; Li, Guo; Lohman, Kurt K.; Musani, Solomon K.; Michael A Nalls; Raffel, Leslie J.; Smith, Jennifer

    2014-01-01

    Age at menopause marks the end of a woman's reproductive life and its timing associates with risks for cancer, cardiovascular and bone disorders. GWAS and candidate gene studies conducted in women of European ancestry have identified 27 loci associated with age at menopause. The relevance of these loci to women of African ancestry has not been previously studied. We therefore sought to uncover additional menopause loci and investigate the relevance of European menopause loci by performing a G...

  17. Pharmacogenomic Genome-Wide Meta-Analysis of Blood Pressure Response to β-Blockers in Hypertensive African Americans.

    Science.gov (United States)

    Gong, Yan; Wang, Zhiying; Beitelshees, Amber L; McDonough, Caitrin W; Langaee, Taimour Y; Hall, Karen; Schmidt, Siegfried O F; Curry, Robert W; Gums, John G; Bailey, Kent R; Boerwinkle, Eric; Chapman, Arlene B; Turner, Stephen T; Cooper-DeHoff, Rhonda M; Johnson, Julie A

    2016-03-01

    African Americans suffer a higher prevalence of hypertension compared with other racial/ethnic groups. In this study, we performed a pharmacogenomic genome-wide association study of blood pressure (BP) response to β-blockers in African Americans with uncomplicated hypertension. Genome-wide meta-analysis was performed in 318 African American hypertensive participants in the 2 Pharmacogenomic Evaluation of Antihypertensive Responses studies: 150 treated with atenolol monotherapy and 168 treated with metoprolol monotherapy. The analysis adjusted for age, sex, baseline BP and principal components for ancestry. Genome-wide significant variants with Pmetoprolol monotherapy, and atenolol add-on therapy: -9.3 versus -4.6, -9.6 versus -4.8, and -9.7 versus -6.4 mm Hg, respectively (3-group meta-analysis P=2.5×10(-8), β=-4.42 mm Hg per variant allele). Similarly, LRRC15 rs11313667 was validated for systolic BP response to β-blocker therapy with 3-group meta-analysis P=7.2×10(-8) and β=-3.65 mm Hg per variant allele. In this first pharmacogenomic genome-wide meta-analysis of BP response to β-blockers in African Americans, we identified novel variants that may provide valuable information for personalized antihypertensive treatment in this group. PMID:26729753

  18. Genome-Wide Association of the Laboratory-Based Nicotine Metabolite Ratio in Three Ancestries

    Science.gov (United States)

    Baurley, James W.; Edlund, Christopher K.; Pardamean, Carissa I.; Conti, David V.; Krasnow, Ruth; Javitz, Harold S.; Hops, Hyman; Swan, Gary E.; Benowitz, Neal L.

    2016-01-01

    Introduction: Metabolic enzyme variation and other patient and environmental characteristics influence smoking behaviors, treatment success, and risk of related disease. Population-specific variation in metabolic genes contributes to challenges in developing and optimizing pharmacogenetic interventions. We applied a custom genome-wide genotyping array for addiction research (Smokescreen), to three laboratory-based studies of nicotine metabolism with oral or venous administration of labeled nicotine and cotinine, to model nicotine metabolism in multiple populations. The trans-3′-hydroxycotinine/cotinine ratio, the nicotine metabolite ratio (NMR), was the nicotine metabolism measure analyzed. Methods: Three hundred twelve individuals of self-identified European, African, and Asian American ancestry were genotyped and included in ancestry-specific genome-wide association scans (GWAS) and a meta-GWAS analysis of the NMR. We modeled natural-log transformed NMR with covariates: principal components of genetic ancestry, age, sex, body mass index, and smoking status. Results: African and Asian American NMRs were statistically significantly (P values ≤ 5E-5) lower than European American NMRs. Meta-GWAS analysis identified 36 genome-wide significant variants over a 43 kilobase pair region at CYP2A6 with minimum P = 2.46E-18 at rs12459249, proximal to CYP2A6. Additional minima were located in intron 4 (rs56113850, P = 6.61E-18) and in the CYP2A6-CYP2A7 intergenic region (rs34226463, P = 1.45E-12). Most (34/36) genome-wide significant variants suggested reduced CYP2A6 activity; functional mechanisms were identified and tested in knowledge-bases. Conditional analysis resulted in intergenic variants of possible interest (P values genome-wide association of CYP2A6 single nucleotide and insertion–deletion polymorphisms. We identify three regions of genome-wide significance: proximal, intronic, and distal to CYP2A6. We replicate the top-ranking single nucleotide polymorphism

  19. Introduction and Rollout of a New Group A Meningococcal Conjugate Vaccine (PsA-TT) in African Meningitis Belt Countries, 2010–2014

    Science.gov (United States)

    Djingarey, Mamoudou H.; Diomandé, Fabien V. K.; Barry, Rodrigue; Kandolo, Denis; Shirehwa, Florence; Lingani, Clement; Novak, Ryan T.; Tevi-Benissan, Carol; Perea, William; Preziosi, Marie-Pierre; LaForce, F. Marc

    2015-01-01

    Background. A group A meningococcal conjugate vaccine (PsA-TT) was developed specifically for the African “meningitis belt” and was prequalified by the World Health Organization (WHO) in June 2010. The vaccine was first used widely in Burkina Faso, Mali, and Niger in December 2010 with great success. The remaining 23 meningitis belt countries wished to use this new vaccine. Methods. With the help of African countries, WHO developed a prioritization scheme and used or adapted existing immunization guidelines to mount PsA-TT vaccination campaigns. Vaccine requirements were harmonized with the Serum Institute of India, Ltd. Results. Burkina Faso was the first country to fully immunize its 1- to 29-year-old population in December 2010. Over the next 4 years, vaccine coverage was extended to 217 million Africans living in 15 meningitis belt countries. Conclusions. The new group A meningococcal conjugate vaccine was well received, with country coverage rates ranging from 85% to 95%. The rollout proceeded smoothly because countries at highest risk were immunized first while attention was paid to geographic contiguity to maximize herd protection. Community participation was exemplary. PMID:26553672

  20. Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility.

    Science.gov (United States)

    Mahajan, Anubha; Go, Min Jin; Zhang, Weihua; Below, Jennifer E; Gaulton, Kyle J; Ferreira, Teresa; Horikoshi, Momoko; Johnson, Andrew D; Ng, Maggie C Y; Prokopenko, Inga; Saleheen, Danish; Wang, Xu; Zeggini, Eleftheria; Abecasis, Goncalo R; Adair, Linda S; Almgren, Peter; Atalay, Mustafa; Aung, Tin; Baldassarre, Damiano; Balkau, Beverley; Bao, Yuqian; Barnett, Anthony H; Barroso, Ines; Basit, Abdul; Been, Latonya F; Beilby, John; Bell, Graeme I; Benediktsson, Rafn; Bergman, Richard N; Boehm, Bernhard O; Boerwinkle, Eric; Bonnycastle, Lori L; Burtt, Noël; Cai, Qiuyin; Campbell, Harry; Carey, Jason; Cauchi, Stephane; Caulfield, Mark; Chan, Juliana C N; Chang, Li-Ching; Chang, Tien-Jyun; Chang, Yi-Cheng; Charpentier, Guillaume; Chen, Chien-Hsiun; Chen, Han; Chen, Yuan-Tsong; Chia, Kee-Seng; Chidambaram, Manickam; Chines, Peter S; Cho, Nam H; Cho, Young Min; Chuang, Lee-Ming; Collins, Francis S; Cornelis, Marylin C; Couper, David J; Crenshaw, Andrew T; van Dam, Rob M; Danesh, John; Das, Debashish; de Faire, Ulf; Dedoussis, George; Deloukas, Panos; Dimas, Antigone S; Dina, Christian; Doney, Alex S; Donnelly, Peter J; Dorkhan, Mozhgan; van Duijn, Cornelia; Dupuis, Josée; Edkins, Sarah; Elliott, Paul; Emilsson, Valur; Erbel, Raimund; Eriksson, Johan G; Escobedo, Jorge; Esko, Tonu; Eury, Elodie; Florez, Jose C; Fontanillas, Pierre; Forouhi, Nita G; Forsen, Tom; Fox, Caroline; Fraser, Ross M; Frayling, Timothy M; Froguel, Philippe; Frossard, Philippe; Gao, Yutang; Gertow, Karl; Gieger, Christian; Gigante, Bruna; Grallert, Harald; Grant, George B; Grrop, Leif C; Groves, Chrisropher J; Grundberg, Elin; Guiducci, Candace; Hamsten, Anders; Han, Bok-Ghee; Hara, Kazuo; Hassanali, Neelam; Hattersley, Andrew T; Hayward, Caroline; Hedman, Asa K; Herder, Christian; Hofman, Albert; Holmen, Oddgeir L; Hovingh, Kees; Hreidarsson, Astradur B; Hu, Cheng; Hu, Frank B; Hui, Jennie; Humphries, Steve E; Hunt, Sarah E; Hunter, David J; Hveem, Kristian; Hydrie, Zafar I; Ikegami, Hiroshi; Illig, Thomas; Ingelsson, Erik; Islam, Muhammed; Isomaa, Bo; Jackson, Anne U; Jafar, Tazeen; James, Alan; Jia, Weiping; Jöckel, Karl-Heinz; Jonsson, Anna; Jowett, Jeremy B M; Kadowaki, Takashi; Kang, Hyun Min; Kanoni, Stavroula; Kao, Wen Hong L; Kathiresan, Sekar; Kato, Norihiro; Katulanda, Prasad; Keinanen-Kiukaanniemi, Kirkka M; Kelly, Ann M; Khan, Hassan; Khaw, Kay-Tee; Khor, Chiea-Chuen; Kim, Hyung-Lae; Kim, Sangsoo; Kim, Young Jin; Kinnunen, Leena; Klopp, Norman; Kong, Augustine; Korpi-Hyövälti, Eeva; Kowlessur, Sudhir; Kraft, Peter; Kravic, Jasmina; Kristensen, Malene M; Krithika, S; Kumar, Ashish; Kumate, Jesus; Kuusisto, Johanna; Kwak, Soo Heon; Laakso, Markku; Lagou, Vasiliki; Lakka, Timo A; Langenberg, Claudia; Langford, Cordelia; Lawrence, Robert; Leander, Karin; Lee, Jen-Mai; Lee, Nanette R; Li, Man; Li, Xinzhong; Li, Yun; Liang, Junbin; Liju, Samuel; Lim, Wei-Yen; Lind, Lars; Lindgren, Cecilia M; Lindholm, Eero; Liu, Ching-Ti; Liu, Jian Jun; Lobbens, Stéphane; Long, Jirong; Loos, Ruth J F; Lu, Wei; Luan, Jian'an; Lyssenko, Valeriya; Ma, Ronald C W; Maeda, Shiro; Mägi, Reedik; Männisto, Satu; Matthews, David R; Meigs, James B; Melander, Olle; Metspalu, Andres; Meyer, Julia; Mirza, Ghazala; Mihailov, Evelin; Moebus, Susanne; Mohan, Viswanathan; Mohlke, Karen L; Morris, Andrew D; Mühleisen, Thomas W; Müller-Nurasyid, Martina; Musk, Bill; Nakamura, Jiro; Nakashima, Eitaro; Navarro, Pau; Ng, Peng-Keat; Nica, Alexandra C; Nilsson, Peter M; Njølstad, Inger; Nöthen, Markus M; Ohnaka, Keizo; Ong, Twee Hee; Owen, Katharine R; Palmer, Colin N A; Pankow, James S; Park, Kyong Soo; Parkin, Melissa; Pechlivanis, Sonali; Pedersen, Nancy L; Peltonen, Leena; Perry, John R B; Peters, Annette; Pinidiyapathirage, Janini M; Platou, Carl G; Potter, Simon; Price, Jackie F; Qi, Lu; Radha, Venkatesan; Rallidis, Loukianos; Rasheed, Asif; Rathman, Wolfgang; Rauramaa, Rainer; Raychaudhuri, Soumya; Rayner, N William; Rees, Simon D; Rehnberg, Emil; Ripatti, Samuli; Robertson, Neil; Roden, Michael; Rossin, Elizabeth J; Rudan, Igor; Rybin, Denis; Saaristo, Timo E; Salomaa, Veikko; Saltevo, Juha; Samuel, Maria; Sanghera, Dharambir K; Saramies, Jouko; Scott, James; Scott, Laura J; Scott, Robert A; Segrè, Ayellet V; Sehmi, Joban; Sennblad, Bengt; Shah, Nabi; Shah, Sonia; Shera, A Samad; Shu, Xiao Ou; Shuldiner, Alan R; Sigurđsson, Gunnar; Sijbrands, Eric; Silveira, Angela; Sim, Xueling; Sivapalaratnam, Suthesh; Small, Kerrin S; So, Wing Yee; Stančáková, Alena; Stefansson, Kari; Steinbach, Gerald; Steinthorsdottir, Valgerdur; Stirrups, Kathleen; Strawbridge, Rona J; Stringham, Heather M; Sun, Qi; Suo, Chen; Syvänen, Ann-Christine; Takayanagi, Ryoichi; Takeuchi, Fumihiko; Tay, Wan Ting; Teslovich, Tanya M; Thorand, Barbara; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Tikkanen, Emmi; Trakalo, Joseph; Tremoli, Elena; Trip, Mieke D; Tsai, Fuu Jen; Tuomi, Tiinamaija; Tuomilehto, Jaakko; Uitterlinden, Andre G; Valladares-Salgado, Adan; Vedantam, Sailaja; Veglia, Fabrizio; Voight, Benjamin F; Wang, Congrong; Wareham, Nicholas J; Wennauer, Roman; Wickremasinghe, Ananda R; Wilsgaard, Tom; Wilson, James F; Wiltshire, Steven; Winckler, Wendy; Wong, Tien Yin; Wood, Andrew R; Wu, Jer-Yuarn; Wu, Ying; Yamamoto, Ken; Yamauchi, Toshimasa; Yang, Mingyu; Yengo, Loic; Yokota, Mitsuhiro; Young, Robin; Zabaneh, Delilah; Zhang, Fan; Zhang, Rong; Zheng, Wei; Zimmet, Paul Z; Altshuler, David; Bowden, Donald W; Cho, Yoon Shin; Cox, Nancy J; Cruz, Miguel; Hanis, Craig L; Kooner, Jaspal; Lee, Jong-Young; Seielstad, Mark; Teo, Yik Ying; Boehnke, Michael; Parra, Esteban J; Chambers, Jonh C; Tai, E Shyong; McCarthy, Mark I; Morris, Andrew P

    2014-03-01

    To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We observed a significant excess in the directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven new T2D susceptibility loci. Furthermore, we observed considerable improvements in the fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterization of complex trait loci and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry. PMID:24509480

  1. Multiplex genotyping system for efficient inference of matrilineal genetic ancestry with continental resolution

    NARCIS (Netherlands)

    M. van Oven (Mannis); M. Vermeulen (Mark); M.H. Kayser (Manfred)

    2011-01-01

    textabstractAbstract Background: In recent years, phylogeographic studies have produced detailed knowledge on the worldwide distribution of mitochondrial DNA (mtDNA) variants, linking specific clades of the mtDNA phylogeny with certain geographic areas. However, a multiplex genotyping system for the

  2. The landscape of recombination in African Americans

    OpenAIRE

    Anjali G Hinch; Tandon, Arti; Patterson, Nick; Song, Yunli; Rohland, Nadin; Palmer, Cameron D; Chen, Gary K.; Wang, Kai; Buxbaum, Sarah G.; Akylbekova, Meggie; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.

    2011-01-01

    Recombination, together with mutation, is the ultimate source of genetic variation in populations. We leverage the recent mixture of people of African and European ancestry in the Americas to build a genetic map measuring the probability of crossing-over at each position in the genome, based on about 2.1 million crossovers in 30,000 unrelated African Americans. At intervals of more than three megabases it is nearly identical to a map built in Europeans. At finer scales it differs significantl...

  3. Counting the Founders: The Matrilineal Genetic Ancestry of the Jewish Diaspora

    Science.gov (United States)

    Behar, Doron M.; Metspalu, Ene; Kivisild, Toomas; Rosset, Saharon; Tzur, Shay; Hadid, Yarin; Yudkovsky, Guennady; Rosengarten, Dror; Pereira, Luisa; Amorim, Antonio; Kutuev, Ildus; Gurwitz, David; Bonne-Tamir, Batsheva; Villems, Richard; Skorecki, Karl

    2008-01-01

    The history of the Jewish Diaspora dates back to the Assyrian and Babylonian conquests in the Levant, followed by complex demographic and migratory trajectories over the ensuing millennia which pose a serious challenge to unraveling population genetic patterns. Here we ask whether phylogenetic analysis, based on highly resolved mitochondrial DNA (mtDNA) phylogenies can discern among maternal ancestries of the Diaspora. Accordingly, 1,142 samples from 14 different non-Ashkenazi Jewish communities were analyzed. A list of complete mtDNA sequences was established for all variants present at high frequency in the communities studied, along with high-resolution genotyping of all samples. Unlike the previously reported pattern observed among Ashkenazi Jews, the numerically major portion of the non-Ashkenazi Jews, currently estimated at 5 million people and comprised of the Moroccan, Iraqi, Iranian and Iberian Exile Jewish communities showed no evidence for a narrow founder effect, which did however characterize the smaller and more remote Belmonte, Indian and the two Caucasus communities. The Indian and Ethiopian Jewish sample sets suggested local female introgression, while mtDNAs in all other communities studied belong to a well-characterized West Eurasian pool of maternal lineages. Absence of sub-Saharan African mtDNA lineages among the North African Jewish communities suggests negligible or low level of admixture with females of the host populations among whom the African haplogroup (Hg) L0-L3 sub-clades variants are common. In contrast, the North African and Iberian Exile Jewish communities show influence of putative Iberian admixture as documented by mtDNA Hg HV0 variants. These findings highlight striking differences in the demographic history of the widespread Jewish Diaspora. PMID:18446216

  4. Genome-Wide SNP Analysis of Southern African Populations Provides New Insights into the Dispersal of Bantu-Speaking Groups

    Science.gov (United States)

    González-Santos, Miguel; Montinaro, Francesco; Oosthuizen, Ockie; Oosthuizen, Erica; Busby, George B.J.; Anagnostou, Paolo; Destro-Bisol, Giovanni; Pascali, Vincenzo; Capelli, Cristian

    2015-01-01

    The expansion of Bantu-speaking agropastoralist populations had a great impact on the genetic, linguistic, and cultural variation of sub-Saharan Africa. It is generally accepted that Bantu languages originated in an area around the present border between Cameroon and Nigeria approximately 5,000 years ago, from where they spread South and East becoming the largest African linguistic branch. The demic consequences of this event are reflected in the relatively high genetic homogeneity observed across most of sub-Saharan Africa populations. In this work, we explored genome-wide single nucleotide polymorphism data from 28 populations to characterize the genetic components present in sub-Saharan African populations. Combining novel data from four Southern African populations with previously published results, we reject the hypothesis that the “non-Bantu” genetic component reported in South-Eastern Africa (Mozambique) reflects extensive gene flow between incoming agriculturalist and resident hunter-gatherer communities. We alternatively suggest that this novel component is the result of demographic dynamics associated with the Bantu dispersal. PMID:26363465

  5. African therapy for a fractured world(view: The life of founder bishop Johannes Richmond and the invention of tradition and group cohesion in an African Initiated Church

    Directory of Open Access Journals (Sweden)

    Cas Wepener

    2015-03-01

    Full Text Available In the book The invention of tradition historian Eric Hobsbawm claims that the process of the invention of tradition serves the formation of group cohesion. The different versions of the life story of the founder bishop of the Corinthian Church of South Africa (AIC, as documented during many years of conducting qualitative field work in this church, are used in this article as a case study in this regard. The article unpacks the way in which the invention of tradition as a process is in this particular AIC currently a work in progress contributing to the formation of a particular type of group cohesion that stretches over racial, religious and denominational boundaries especially by means of the unique liturgical rituals that were influenced by the life story of the founder. The group cohesion that this process fosters is in essence aimed at healing in all its multifaceted dimensions, which includes healing from physical ailments, ‘healing’ from barrenness, healing from spirit possession to healing as (re-incorporation of an individual into the larger group, the healing of a nation as well as healing from a dualistic spirit-matter worldview.

  6. CCR2-V64I polymorphism is associated with increased risk of cervical cancer but not with HPV infection or pre-cancerous lesions in African women

    International Nuclear Information System (INIS)

    Cervical cancer, caused by specific oncogenic types of human papillomavirus (HPV), is the second most common cancer in women worldwide. A large number of young sexually active women get infected by HPV but only a small fraction of them have persistent infection and develop cervical cancer pointing to co- factors including host genetics that might play a role in outcome of the HPV infection. This study investigated the role of CCR2-V64I polymorphism in cervical cancer, pre-cancers and HPV infection in South African women resident in Western Cape. CCR2-V64I polymorphism has been previously reported to influence the progression to cervical cancer in some populations and has also been associated with decreased progression from HIV infection to AIDS. Genotyping for CCR2-V64I was done by PCR-SSP in a case-control study of 446 women (106 black African and 340 mixed-ancestry) with histologically confirmed invasive cervical cancer and 1432 controls (322 black African and 1110 mixed-ancestry) group-matched (1:3) by age, ethnicity and domicile status. In the control women HPV was detected using the Digene Hybrid Capture II test and cervical disease was detected by cervical cytology. The CCR2-64I variant was significantly associated with cervical cancer when cases were compared to the control group (P = 0.001). Further analysis comparing selected groups within the controls showed that individuals with abnormal cytology and high grade squamous intraepitleial neoplasia (HSIL) did not have this association when compared to women with normal cytology. HPV infection also showed no association with CCR2-64I variant. Comparing SIL positive controls with the cases showed a significant association of CCR2-64I variant (P = 0.001) with cervical cancer. This is the first study of the role of CCR2-V64I polymorphism in cervical cancer in an African population. Our results show that CCR2-64I variant is associated with the risk of cervical cancer but does not affect the susceptibility to HPV

  7. Enhanced Statistical Tests for GWAS in Admixed Populations: Assessment using African Americans from CARe and a Breast Cancer Consortium

    OpenAIRE

    Pasaniuc, Bogdan; Zaitlen, Noah; Lettre, Guillaume; Chen, Gary K.; Tandon, Arti; Kao, W. H. Linda; Ruczinski, Ingo; Fornage, Myriam; Siscovick, David S; Zhu, Xiaofeng; Larkin, Emma; Lange, Leslie A.; Cupples, L. Adrienne; Yang, Qiong; Akylbekova, Ermeg L.

    2011-01-01

    While genome-wide association studies (GWAS) have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD) exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD) due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously consi...

  8. Enhanced statistical tests for GWAS in admixed populations: assessment using African Americans from CARe and a Breast Cancer Consortium.

    OpenAIRE

    Bogdan Pasaniuc; Noah Zaitlen; Guillaume Lettre; Chen, Gary K.; Arti Tandon; Linda Kao, W H; Ingo Ruczinski; Myriam Fornage; Siscovick, David S; Xiaofeng Zhu; Emma Larkin; Lange, Leslie A.; L Adrienne Cupples; Qiong Yang; Akylbekova, Ermeg L.

    2011-01-01

    While genome-wide association studies (GWAS) have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD) exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD) due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously consi...

  9. African therapy for a fractured world(view): The life of founder bishop Johannes Richmond and the invention of tradition and group cohesion in an African Initiated Church

    OpenAIRE

    Cas Wepener

    2015-01-01

    In the book The invention of tradition historian Eric Hobsbawm claims that the process of the invention of tradition serves the formation of group cohesion. The different versions of the life story of the founder bishop of the Corinthian Church of South Africa (AIC), as documented during many years of conducting qualitative field work in this church, are used in this article as a case study in this regard. The article unpacks the way in which the invention of tradition as a process is in th...

  10. Continental Divide Trail

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This shapefile was created to show the proximity of the Continental Divide to the Continental Divide National Scenic Trail in New Mexico. This work was done as part...

  11. Manifestations of Differential Cultural Capital in a University Classroom: Views from Classroom Observations and Focus Group Discussions in a South African University

    Directory of Open Access Journals (Sweden)

    Edmore Mutekwe

    2014-11-01

    Full Text Available Based predominantly on Pierre Bourdieu’s social and cultural reproduction theory, particularly his notions of cultural capital and symbolic violence, this paper explores how first year post graduate Diploma in Higher Education (PGDHE university students from diverse socio-linguistic backgrounds differ in the levels at which they understand and express themselves in classroom activities. The paper’s thesis is that the diverse nature of South African classrooms presents a number of challenges not only for students but also for educators in terms of the use of English as a medium of instruction or the language for learning and teaching (LOLT. Owing to the fact that the South African Language in Education Policy (LiEP of 1997 empowers both learners and educators in schools to use any of the eleven South African official languages as a LOLT wherever that is reasonably possible, students whose English backgrounds were deficient in enculturating them in the use of English as a learning tool often encounter challenges in expressing their ideas in the classroom, whether in writing or in oral presentations. The discussion is anchored in the data elicited through two data collection methods, lesson observations in a Diploma in Higher Education, Research class composed of students from diverse racial and ethnic backgrounds and through focus group discussion sessions with 40 multi-ethnic Diploma in Higher Education students from the same classroom. The data management and analysis for this study was done thematically, with views emerging from the observations and focus group discussions being clustered into superordinate themes for convenience of the discussion of the findings. The findings of this study were that students from affluent socio-economic backgrounds who enter university with a rich and relevant English linguistic capital, values and attitudes enjoy an enormous advantage compared to their counterparts whose social class and linguistic

  12. Observational monitoring of clinical signs during the last stage of habituation in a wild western gorilla group at Bai Hokou, Central African Republic.

    Science.gov (United States)

    Morton, F Blake; Todd, Angelique F; Lee, Phyllis; Masi, Shelly

    2013-01-01

    Anthropozoonotic disease transmission to great apes is a critical conservation concern, and has raised ethical doubts regarding ape habituation. We monitored over a 3-year period clinical signs within a group of wild western gorillas (G. gorilla) undergoing habituation at Bai Hokou, Central African Republic. The majority of observations consisted of singular coughs and sneezes among the gorillas. These were the only clinical signs that significantly and positively increased over the years. No changes in the demography of the study group were observed. While clinical signs are not necessarily indicative of 'disease' or other health-related problems, we discuss how long-term records of clinical signs provide useful information when health monitoring, and the importance of the rigid application of preventive disease transmission protocols. PMID:23736676

  13. Worldwide F-ST Estimates Relative to Five Continental-Scale Populations

    OpenAIRE

    Steele, C. D.; Court, D. S.; Balding, D. J.

    2014-01-01

    We estimate the population genetics parameter inline image (also referred to as the fixation index) from short tandem repeat (STR) allele frequencies, comparing many worldwide human subpopulations at approximately the national level with continental-scale populations. inline image is commonly used to measure population differentiation, and is important in forensic DNA analysis to account for remote shared ancestry between a suspect and an alternative source of the DNA. We estimate inline imag...

  14. Empirical testing of a 23-AIMs panel of SNPs for ancestry evaluations in four major US populations.

    Science.gov (United States)

    Zeng, Xiangpei; Warshauer, David H; King, Jonathan L; Churchill, Jennifer D; Chakraborty, Ranajit; Budowle, Bruce

    2016-07-01

    Ancestry informative markers (AIMs) can be used to determine population affiliation of the donors of forensic samples. In order to examine ancestry evaluations of the four major populations in the USA, 23 highly informative AIMs were identified from the International HapMap project. However, the efficacy of these 23 AIMs could not be fully evaluated in silico. In this study, these 23 SNPs were multiplexed to test their actual performance in ancestry evaluations. Genotype data were obtained from 189 individuals collected from four American populations. One SNP (rs12149261) on chromosome 16 was removed from this panel because it was duplicated on chromosome 1. The resultant 22-AIMs panel was able to empirically resolve the four major populations as in the in silico study. Eight individuals were assigned to a different group than indicated on their samples. The assignments of the 22 AIMs for these samples were consistent with AIMs results from the ForenSeq(TM) panel. No departures from Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) were detected for all 22 SNPs in four US populations (after removing the eight problematic samples). The principal component analysis (PCA) results indicated that 181 individuals from these populations were assigned to the expected groups. These 22 SNPs can contribute to the candidate AIMs pool for potential forensic identification purposes in major US populations. PMID:26914801

  15. Malagasy Genetic Ancestry Comes from an Historical Malay Trading Post in Southeast Borneo.

    Science.gov (United States)

    Brucato, Nicolas; Kusuma, Pradiptajati; Cox, Murray P; Pierron, Denis; Purnomo, Gludhug A; Adelaar, Alexander; Kivisild, Toomas; Letellier, Thierry; Sudoyo, Herawati; Ricaut, François-Xavier

    2016-09-01

    Malagasy genetic diversity results from an exceptional protoglobalization process that took place over a thousand years ago across the Indian Ocean. Previous efforts to locate the Asian origin of Malagasy highlighted Borneo broadly as a potential source, but so far no firm source populations were identified. Here, we have generated genome-wide data from two Southeast Borneo populations, the Banjar and the Ngaju, together with published data from populations across the Indian Ocean region. We find strong support for an origin of the Asian ancestry of Malagasy among the Banjar. This group emerged from the long-standing presence of a Malay Empire trading post in Southeast Borneo, which favored admixture between the Malay and an autochthonous Borneo group, the Ma'anyan. Reconciling genetic, historical, and linguistic data, we show that the Banjar, in Malay-led voyages, were the most probable Asian source among the analyzed groups in the founding of the Malagasy gene pool. PMID:27381999

  16. Phylogenomic evidence of adaptive evolution in the ancestry of humans

    OpenAIRE

    Goodman, Morris; Sterner, Kirstin N.

    2010-01-01

    In Charles Darwin’s tree model for life’s evolution, natural selection adaptively modifies newly arisen species as they branch apart from their common ancestor. In accord with this Darwinian concept, the phylogenomic approach to elucidating adaptive evolution in genes and genomes in the ancestry of modern humans requires a well supported and well sampled phylogeny that accurately places humans and other primates and mammals with respect to one another. For more than a century, first from the ...

  17. Infinitely long branches and an informal test of common ancestry

    OpenAIRE

    de Oliveira Martins, Leonardo; Posada, David

    2016-01-01

    Background The evidence for universal common ancestry (UCA) is vast and persuasive. A phylogenetic test has been proposed for quantifying its odds against independently originated sequences based on the comparison between one versus several trees. This test was successfully applied to a well-supported homologous sequence alignment, which was however criticized on the basis of simulations showing that alignments without any phylogenetic structure could mislead its conclusions. Results Here we ...

  18. A quasi-exclusive European ancestry in the Senepol tropical cattle breed highlights the importance of the slick locus in tropical adaptation.

    Directory of Open Access Journals (Sweden)

    Laurence Flori

    Full Text Available BACKGROUND: The Senepol cattle breed (SEN was created in the early XX(th century from a presumed cross between a European (EUT breed (Red Poll and a West African taurine (AFT breed (N'Dama. Well adapted to tropical conditions, it is also believed trypanotolerant according to its putative AFT ancestry. However, such origins needed to be verified to define relevant husbandry practices and the genetic background underlying such adaptation needed to be characterized. METHODOLOGY/PRINCIPAL FINDINGS: We genotyped 153 SEN individuals on 47,365 SNPs and combined the resulting data with those available on 18 other populations representative of EUT, AFT and Zebu (ZEB cattle. We found on average 89% EUT, 10.4% ZEB and 0.6% AFT ancestries in the SEN genome. We further looked for footprints of recent selection using standard tests based on the extent of haplotype homozygosity. We underlined i three footprints on chromosome (BTA 01, two of which are within or close to the polled locus underlying the absence of horns and ii one footprint on BTA20 within the slick hair coat locus, involved in thermotolerance. Annotation of these regions allowed us to propose three candidate genes to explain the observed signals (TIAM1, GRIK1 and RAI14. CONCLUSIONS/SIGNIFICANCE: Our results do not support the accepted concept about the AFT origin of SEN breed. Initial AFT ancestry (if any might have been counter-selected in early generations due to breeding objectives oriented in particular toward meat production and hornless phenotype. Therefore, SEN animals are likely susceptible to African trypanosomes which questions the importation of SEN within the West African tsetse belt, as promoted by some breeding societies. Besides, our results revealed that SEN breed is predominantly a EUT breed well adapted to tropical conditions and confirmed the importance in thermotolerance of the slick locus.

  19. Assimilation Differences among Africans in America.

    Science.gov (United States)

    Dodoo, F. Nii-Amoo

    1997-01-01

    Census data (1990) indicate that male African immigrants earn more than their Caribbean-born counterparts or native-born African Americans, but controlling for relevant earnings-related endowments erases the African advantage and elevates Caribbean earnings above those of the other groups. Also, African (but not Caribbean) university degree…

  20. Ancestry of the Australian termitivorous numbat.

    Science.gov (United States)

    Zemann, Anja; Churakov, Gennady; Donnellan, Stephen; Grützner, Frank; Zhao, Fangqing; Brosius, Jürgen; Schmitz, Jürgen

    2013-05-01

    The Australian numbat, Myrmecobius fasciatus, is the only marsupial that feeds almost exclusively on termites and that has a life following the diurnally restricted and dynamic geographical distribution of termites. The millions of years of this adaptation led to unique morphological and anatomical features, especially basicranial and dental characteristics, that make it difficult to identify a clear phylogenetic affiliation to other marsupials. From DNA sequence analyses, the family Myrmecobiidae is placed within the dasyuromorph marsupials, but the exact position varies from study to study, and support values are mostly rather modest. Here, we report the recovery and analysis of approximately 110,000 quasifossilized traces of mobile element insertions into the genome of a dasyurid marsupial (Tasmanian devil), 25 of which are phylogenetically informative for early dasyuromorphial evolution. Fourteen of these ancient retroposon insertions are shared by the 16 Dasyuromorphia species analyzed, including the numbat, but are absent in the outgroups. An additional 11 other insertions are present in all Dasyuridae but are absent in the numbat. These findings place numbats as the sister group to all living Dasyuridae and show that the investigated Dasyuromorphia, including the Myrmecobiidae, constitutes a monophyletic group that is separated from Peramelemorphia, Notoryctemorphia, and other marsupials. PMID:23429857

  1. Continental margins: linking ecosystems

    OpenAIRE

    Kelly-Gerreyn, Boris; Rabalais, Nancy; Middelburg, Jack; Roy, Sylvie; Liu, Kon-Kee; Thomas, Helmut; Zhang, Jing

    2008-01-01

    Impacts of Global, Local and Human Forcings on Biogeochemical Cycles and Ecosystems, IMBER/LOICZ Continental Margins Open Science Conference; Shanghai, China, 17–21 September 2007; More than 100 scientists from 25 countries came together to address global, regional, local, and human pressures interactively affecting continental margin biogeochemical cycles, marine food webs, and society. Continental margins cover only 12% of the global ocean area yet account for more than 30% of global oceani...

  2. FGFR2 and other loci identified in genome-wide association studies are associated with breast cancer in African-American and younger women

    OpenAIRE

    Barnholtz-Sloan, Jill S; Shetty, Priya B; Guan, Xiaowei; Nyante, Sarah J; Luo, Jingchun; Brennan, Donal J.; Millikan, Robert C.

    2010-01-01

    Twenty-nine single-nucleotide polymorphisms (SNPs) from previously published genome-wide association studies (GWAS) and multiple ancestry informative markers were genotyped in the Carolina Breast Cancer Study (CBCS) (742 African-American (AA) cases, 1230 White cases; 658 AA controls, 1118 White controls). In the entire study population, 9/10 SNPs in fibroblast growth factor receptor 2 (FGFR2) were significantly associated with breast cancer after adjusting for age, race and European ancestry ...

  3. From Bows to Sound-Chests: Tracing the Ancestry of the Violin

    Directory of Open Access Journals (Sweden)

    Janelle R. Finley

    2016-04-01

    Full Text Available The ancestry of the violin is a subject that has been studied, researched, debated, and written about in great detail. However, despite all of the research and study, the ancestry of the violin is still not certain. This paper presents two schools of thought that propose different theories as to how the ancestry of the violin should be determined and what instruments should be included in the ancestry of the violin. The first school of thought proposes that the violin’s ancestry should be traced through the bow. The second theory proposes that the violin’s ancestry should be traced through the sound-chest of the violin. This paper also presents the different arguments for and against each theory, the importance of this topic, and the paper’s position on this topic. Research for this paper was accomplished through the use of scholarly books on the subject of the history of the violin.

  4. Africanization of a feral honey bee (Apis mellifera) population in South Texas: does a decade make a difference?

    Science.gov (United States)

    Rangel, Juliana; Giresi, Melissa; Pinto, Maria Alice; Baum, Kristen A; Rubink, William L; Coulson, Robert N; Johnston, John Spencer

    2016-04-01

    The arrival to the United States of the Africanized honey bee, a hybrid between European subspecies and the African subspecies Apis mellifera scutellata, is a remarkable model for the study of biological invasions. This immigration has created an opportunity to study the dynamics of secondary contact of honey bee subspecies from African and European lineages in a feral population in South Texas. An 11-year survey of this population (1991-2001) showed that mitochondrial haplotype frequencies changed drastically over time from a resident population of eastern and western European maternal ancestry, to a population dominated by the African haplotype. A subsequent study of the nuclear genome showed that the Africanization process included bidirectional gene flow between European and Africanized honey bees, giving rise to a new panmictic mixture of A. m. scutellata- and European-derived genes. In this study, we examined gene flow patterns in the same population 23 years after the first hybridization event occurred. We found 28 active colonies inhabiting 92 tree cavities surveyed in a 5.14 km(2) area, resulting in a colony density of 5.4 colonies/km(2). Of these 28 colonies, 25 were of A. m. scutellata maternal ancestry, and three were of western European maternal ancestry. No colonies of eastern European maternal ancestry were detected, although they were present in the earlier samples. Nuclear DNA revealed little change in the introgression of A. m. scutellata-derived genes into the population compared to previous surveys. Our results suggest this feral population remains an admixed swarm with continued low levels of European ancestry and a greater presence of African-derived mitochondrial genetic composition. PMID:27069571

  5. Development of West African Rainy Seasons (Invited)

    Science.gov (United States)

    Cook, K. H.

    2013-12-01

    The development of West African rainy seasons in the observed climatology can be understood in terms of two factors: continentality, i.e., the shape and placement of the African continent, and solar forcing. First, the observed features of the West African spring and summer precipitation climatology that distinguish it from the precipitation climatology of the tropical Atlantic to the east and Central/Eastern Africa to the west are presented. These include a lingering of the precipitation maximum along the Guinean coast in June and the apparent sudden movement of the precipitation maximum into the Sahel in early July. Then, these distinguishing features of the West Africa precipitation climatology are explained in terms of the regional dynamics and, finally, related to continentality and solar forcing through the roles of the African easterly jet, land surface temperature, and seasonally-varying SSTs.

  6. Statement delivered in the Board of Governors on 28 November 2008 by the Resident Representative of Zimbabwe on behalf of the group of members of the African Union concerning the appointment of the Director General

    International Nuclear Information System (INIS)

    On 28 November 2008, the Resident Representative of Zimbabwe to the Agency delivered a statement in the Board of Governors, on behalf of the group of members of the African Union, concerning the appointment of the Director General. As requested in the statement, the statement is herewith circulated for the information of Member States

  7. New Evidence on the Common Ancestry of Tetrapods and Lungfish

    Institute of Scientific and Technical Information of China (English)

    Zhao Baohua

    2002-01-01

    @@ As reported in a recent issue of Nature (Aug. 15, 2002),two Chinese scientists pinpoint their newly discovered fossil fish as the most direct piece of evi dence on the common ancestry shared by tetrapods (all land verte brates including human beings) and lungfish. This latest advance in studying the origin and evolution of early fishes was jointly made by Professor Zhu Min from the CAS Institute of Vertebrate Paleontology & Paleoanthropology and his colleague Yu Xiaobo, now a Professor at the Biology Department of Kean University (New Jersey, USA).

  8. Respirator fit of a medium mask on a group of South Africans: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Wilson Kerry S

    2011-03-01

    Full Text Available Abstract Background In South Africa, respiratory protective equipment is often the primary control method used to protect workers. This preliminary study investigated how well a common disposable P2 respirator fitted persons with a range of facial dimensions. Methods Quantitative respirator fit tests were performed on 29 volunteers from different racial, gender and face size groups. Two facial dimensions width (bizygomatic and length (menton-sellion were measured for all participants. Results In this study 13.8% of the participants demonstrated a successful fit with the medium sized mask. These included participants from three different racial and both gender groups. The large percentage of failed fit tests (86% indicates that reliance on off-the-shelf respirators could be problematic in South Africa. Conclusions The limitations of this preliminary study notwithstanding, respirator fit appear to be associated with individual facial characteristics and are not specific to racial/ethnic or gender characteristics.

  9. The Hmong Diaspora: preserved South-East Asian genetic ancestry in French Guianese Asians.

    Science.gov (United States)

    Brucato, Nicolas; Mazières, Stéphane; Guitard, Evelyne; Giscard, Pierre-Henri; Bois, Etienne; Larrouy, Georges; Dugoujon, Jean-Michel

    2012-01-01

    The Hmong Diaspora is one of the widest modern human migrations. Mainly localised in South-East Asia, the United States of America, and metropolitan France, a small community has also settled the Amazonian forest of French Guiana. We have biologically analysed 62 individuals of this unique Guianese population through three complementary genetic markers: mitochondrial DNA (HVS-I/II and coding region SNPs), Y-chromosome (SNPs and STRs), and the Gm allotypic system. All genetic systems showed a high conservation of the Asian gene pool (Asian ancestry: mtDNA=100.0%; NRY=99.1%; Gm=96.6%), without a trace of founder effect. When compared across various Asian populations, the highest correlations were observed with Hmong-Mien groups still living in South-East Asia (Fst<0.05; P-value<0.05). Despite a long history punctuated by exodus, the French Guianese Hmong have maintained their original genetic diversity. PMID:23199638

  10. Benefiting Africans

    Institute of Scientific and Technical Information of China (English)

    ZHANG ZHIPING

    2011-01-01

    Along with thriving Sino-African economic and trade ties,Chinese companies have attached greater importance to their social responsibility to Africans.More than 2,000 sweaters woven by Chinese mothers were sent to orphans and disabled children in Kenya and four other African countries in September.This activity was launched by Hengyuanxiang,a leading Chinese wool manufacturer.

  11. Benefiting Africans

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Along with thriving Sino-African economic and trade ties,Chinese companies have attached greater importance to their social responsibility to Africans.More than 2,000 sweaters woven by Chinese mothers were sent to orphans and disabled children in Kenya and four other African countries in September. This activity was launched by Hengyuanxiang,aleading Chinese wool manufacturer.

  12. Respirator fit of a medium mask on a group of South Africans: a cross-sectional study

    OpenAIRE

    Wilson Kerry S; Spies Adri; Ferrie Robert

    2011-01-01

    Abstract Background In South Africa, respiratory protective equipment is often the primary control method used to protect workers. This preliminary study investigated how well a common disposable P2 respirator fitted persons with a range of facial dimensions. Methods Quantitative respirator fit tests were performed on 29 volunteers from different racial, gender and face size groups. Two facial dimensions width (bizygomatic) and length (menton-sellion) were measured for all participants. Resul...

  13. Behavioral responses of one western lowland gorilla (Gorilla gorilla gorilla) group at Bai Hokou, Central African Republic, to tourists, researchers and trackers.

    Science.gov (United States)

    Klailova, Michelle; Hodgkinson, Chloe; Lee, Phyllis C

    2010-09-01

    Gorilla tourism, widely perceived as a lucrative industry, is propelled by strong market demand with programs in five countries and for three of four gorilla subspecies. Human presence may negatively affect wild gorillas, potentially lowering immunity and increasing the likelihood of acquiring human-borne disease. Yet, behavioral impacts of humans on wild gorilla behavior remain largely unexplored, particularly for western lowland gorillas. We evaluate the impact of tourist presence, human observer numbers (tourists, trackers, and researchers), and human observer distance on the behavior of one habituated gorilla group at Bai Hokou, Central African Republic. Behavioral data were collected for more than 12 months from January 2007. Of silverback aggressive events, 39% (N=229) were human directed, but 65% were low-level soft barks. Adult females, and one in particular, were responsible for the highest number of aggressive events toward humans. Humans maintained closer proximity to the silverback when tourists were present, although tourist numbers had no significant impact on overall group activity budgets or rates of human-directed aggression. However, as research team size increased, group feeding rates decreased. Close observer-silverback distance correlated with a decrease in his feeding rates and an increase in human monitoring. He directed less aggression toward observers at distances >10 m, although observers spent 48.5% of time between 6 and 10 m of the silverback. We discuss gorilla personality as a factor in human-directed aggression. We explore whether the current 7 m distance limit governing gorilla tourism, based on disease transmission risks, is sufficient considering the potential behavioral stressor of close human presence. We recommend increasing minimum observation distance to >10 m where possible, decreasing observer group sizes, particularly after a visit consisting of maximum numbers and restricting tourist access to 1 visit/day. PMID:20806337

  14. Chlamydia trachomatis, human immunodeficiency virus (HIV distribution and sexual behaviors across gender and age group in an African setting.

    Directory of Open Access Journals (Sweden)

    Joel Fleury Djoba Siawaya

    Full Text Available OBJECTIVE: The purpose of this study was to (1 describe the distribution of Chlamydia trachomatis (CT and Human Immunodeficiency Virus (HIV cases across gender and age groups in Libreville (Gabon; (2 examine Gabonese Sexually Transmitted Infections (STIs-related risk behaviour. METHODS: The sampled population was people attending the "Laboratoire National de Santé Plublique". Between 2007 and 2011, 14 667 and 9 542 people respectively, were tested for CT and HIV infections. 1 854 of them were tested for both infections. We calculated CT and HIV rates across gender and age groups. Also analysed was the groups' contribution to the general CT and HIV epidemiology. STIs-related risk behaviours were assessed in 224 men and 795 women (between July 2011 and March 2013 who agreed and answered a questionnaire including questions on their marital status, number of sex partners, sexual practices, history of STIs, sex frequency and condom use. RESULTS: Data showed a 24% dropped in the CT infection rate between 2007 and 2010, followed by a 14% increase in 2011. The HIV infection rates for the same period were between 15% and 16%. The risk of a CT-positive subject getting HIV is about 0.71 times the risk of a CT-negative subject. Young adult aged between 18 and 35 years old represented 65.2% of people who had STIs. 80% of women and 66% of men confessed to an inconsistent use of condoms. 11.6% of women and 48% of men declared having multiple sex partners. 61% of questioned women and 67% of men declared knowing their HIV status. CONCLUSIONS: In this Gabonese setting, the population-aged from 18 to 35 years is the most affected by STIs. Other matters of concern are the inconsistent use of protection and sex with non-spousal or non-life partners.

  15. Female genital mutilation in African and African American women's literature

    Directory of Open Access Journals (Sweden)

    Darja Marinšek

    2007-12-01

    Full Text Available The article builds on the existing dispute between African and African American women writers on the competence of writing about female genital mutilation (FGM, and tries to determine the existence and nature of the differences between the writings of these two groups. The author uses comparative analysis of two popular African and African American novels, comparing their ways of describing FGM, its causes and consequences, the level ob objectivity and the style of the narrations.This is followed by a discussion on the reasons for such differences, incorporating a larger circle of both African and African American women authors, at the same time analysing the deviance within the two groups. While the differences between African American writers are not that great, as they mostly fail to present the issue from different points of view, which is often the result of their lack of direct knowledge of the topic, African authors' writing is in itself discovered to be ambivalent and not at all invariable. The reasons for such ambivalence are then discussed in greater context, focusing on the effect of the authors' personal contact with circumcision as well as their knowledge and acceptance of Western values. The author concludes by establishing the African ambivalent attitude towards FGM, which includes different aspects of the issue, as the most significant difference between their and African American writers' description of this practice.

  16. Genome-wide Ancestry Patterns in Rapanui Suggest Pre-European Admixture with Native Americans

    DEFF Research Database (Denmark)

    Moreno-Mayar, J. Víctor; Rasmussen, Simon; Seguin-Orlando, Andaine;

    2014-01-01

    . We found a mostly Polynesian ancestry among Rapanui and detected genome-wide patterns consistent with Native American and European admixture. By considering the distribution of local ancestry tracts of eight unrelated Rapanui, we found statistical support for Native American admixture dating to AD...

  17. Evolutionary ancestry and novel functions of the mammalian glucose transporter (GLUT family

    Directory of Open Access Journals (Sweden)

    Patron Nicola

    2010-05-01

    Full Text Available Abstract Background In general, sugar porters function by proton-coupled symport or facilitative transport modes. Symporters, coupled to electrochemical energy, transport nutrients against a substrate gradient. Facilitative carriers transport sugars along a concentration gradient, thus transport is dependent upon extracellular nutrient levels. Across bacteria, fungi, unicellular non-vertebrates and plants, proton-coupled hexose symport is a crucial process supplying energy under conditions of nutrient flux. In mammals it has been assumed that evolution of whole body regulatory mechanisms would eliminate this need. To determine whether any isoforms bearing this function might be conserved in mammals, we investigated the relationship between the transporters of animals and the proton-coupled hexose symporters found in other species. Results We took a comparative genomic approach and have performed the first comprehensive and statistically supported phylogenetic analysis of all mammalian glucose transporter (GLUT isoforms. Our data reveals the mammalian GLUT proteins segregate into five distinct classes. This evolutionary ancestry gives insight to structure, function and transport mechanisms within the groups. Combined with biological assays, we present novel evidence that, in response to changing nutrient availability and environmental pH, proton-coupled, active glucose symport function is maintained in mammalian cells. Conclusions The analyses show the ancestry, evolutionary conservation and biological importance of the GLUT classes. These findings significantly extend our understanding of the evolution of mammalian glucose transport systems. They also reveal that mammals may have conserved an adaptive response to nutrient demand that would have important physiological implications to cell survival and growth.

  18. Consequences of Abdominal Adiposity within the Metabolic Syndrome Paradigm in Black People of African Ancestry

    OpenAIRE

    Trudy Gaillard

    2014-01-01

    The metabolic syndrome (MetS) is a constellation of risk factors that are associated with increased risks for coronary heart disease and type 2 diabetes. Although the cause is unknown, abdominal adiposity is considered the underpinning of these metabolic alterations. Hence, increased abdominal adiposity contributes to dyslipidemia, hyperglycemia, beta cell dysfunction, insulin resistance, hypertension and inflammation. The role of abdominal adiposity in the causation of metabolic alterations...

  19. Petrology of continental pyroclastic and epiclastic sequences in the Chubut Group (Cretaceous: Los Altares-Las Plumas area, Chubut, Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Marcelo Manassero

    2000-07-01

    The volcaniclastic successions of the Cerro Barcino Formation (Chubut Group, of Aptian-Cenomanian age, crop out on both margins of the Chubut River with a thickness of 200 m. The Middle Member Cerro Castaño (syneruptive, 90 m and the Upper Member, Las Plumas (intereruptive, 110 m are described on the basis of photogeological mapping, sections, and mineralogical, petrographical and geochemical analysis. Paleocurrents are directed to the northeast (Cerro Castaño or north (Las Plumas. An erosive boundary, located at the base of the Las Plumas Member, is reported for the first time in this contribution The pyroclastic rocks are composed, of planar, curviplanar, branching, Y-shaped shards and fibrous pumice fragments. The volcanogenic sedimentary deposits also include, vitric fragments with hematitic pigmentation (Las Plumas. Due to diagenetic processes, the glass fragments are replaced by clay minerals (smectites and scarce illite and zeolites which also appear as cementing material. Within the Cerro Castaño Member, analcime prevails assembled with less clinoptilolite, while in the Las Plumas Member, the abundant clinoptilolite is assembled with scarce analcime and mordenite. Pyroclastic sediments (ash-fall covered extended flat or slightly undulated plains, where discrete sandy rivers flowed. The presence of gravels and sandstones at the base of the Las Plumas Member and wide and shallow braided river channels are associated to tectonic events and seasonability. Eruptions were highly explosive derived from viscous and volatile-rich magmas. The abundance of fine planar and cuspate shards in the tuff suggest that the explosive center was located approximately 500 km probably to the west

  20. Atlas of prostate cancer heritability in European and African-American men pinpoints tissue-specific regulation

    DEFF Research Database (Denmark)

    Gusev, Alexander; Shi, Huwenbo; Kichaev, Gleb;

    2016-01-01

    Although genome-wide association studies have identified over 100 risk loci that explain ∼33% of familial risk for prostate cancer (PrCa), their functional effects on risk remain largely unknown. Here we use genotype data from 59,089 men of European and African American ancestries combined with c...

  1. Spread of pedigree versus genetic ancestry in spatially distributed populations.

    Science.gov (United States)

    Kelleher, J; Etheridge, A M; Véber, A; Barton, N H

    2016-04-01

    Ancestral processes are fundamental to modern population genetics and spatial structure has been the subject of intense interest for many years. Despite this interest, almost nothing is known about the distribution of the locations of pedigree or genetic ancestors. Using both spatially continuous and stepping-stone models, we show that the distribution of pedigree ancestors approaches a travelling wave, for which we develop two alternative approximations. The speed and width of the wave are sensitive to the local details of the model. After a short time, genetic ancestors spread far more slowly than pedigree ancestors, ultimately diffusing out with radius ∼t rather than spreading at constant speed. In contrast to the wave of pedigree ancestors, the spread of genetic ancestry is insensitive to the local details of the models. PMID:26546979

  2. Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior in Côte d'Ivoire

    Directory of Open Access Journals (Sweden)

    Kang Hae Ji

    2011-07-01

    Full Text Available Abstract Background Tanganya virus (TGNV, the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Therese's shrew (Crocidura theresae, and is phylogenetically distinct from Thottapalayam virus (TPMV in the Asian house shrew (Suncus murinus and Imjin virus (MJNV in the Ussuri white-toothed shrew (Crocidura lasiura. The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified. Methods Lung tissues, collected in RNAlater®, from 39 Buettikofer's shrews (Crocidura buettikoferi, 5 Jouvenet's shrews (Crocidura jouvenetae, 9 West African pygmy shrews (Crocidura obscurior and 21 African giant shrews (Crocidura olivieri captured in Côte d'Ivoire during 2009, were systematically examined for hantavirus RNA by RT-PCR. Results A genetically distinct hantavirus, designated Azagny virus (AZGV, was detected in the West African pygmy shrew. Phylogenetic analysis of the S, M and L segments, using maximum-likelihood and Bayesian methods, under the GTR+I+Γ model of evolution, showed that AZGV shared a common ancestry with TGNV and was more closely related to hantaviruses harbored by soricine shrews than to TPMV and MJNV. That is, AZGV in the West African pygmy shrew, like TGNV in the Therese's shrew, did not form a monophyletic group with TPMV and MJNV, which were deeply divergent and basal to other rodent- and soricomorph-borne hantaviruses. Ancestral distributions of each hantavirus lineage, reconstructed using Mesquite 2.74, suggested that the common ancestor of all hantaviruses was most likely of Eurasian, not African, origin. Conclusions Genome-wide analysis of many more hantaviruses from sub-Saharan Africa are required to better understand how the biogeographic origin and radiation of African shrews might have contributed to, or have resulted from, the evolution

  3. Epidemiology, pathology, and genetics of prostate cancer among African Americans compared with other ethnicities.

    Science.gov (United States)

    Williams, Heinric; Powell, Isaac J

    2009-01-01

    Prostate cancer is the most common cancer affecting men in the Western world. In the United States, it is the second leading cause of cancer related deaths after lung and bronchus carcinoma. No definitive causes of prostate cancer (PCa) have been identified to date but, increasing age, a positive family history, and sub-Saharan African ancestry are strongly linked to its development. African American men (AAM) have the highest reported incidence rates in the United States and their mortality from the disease is markedly higher than that of European American men (EAM). Conversely, Asian American men and Pacific Islanders (API), American Indian and Alaskan Native (AI/AN) men, and Hispanic men all have lower incidence and mortality rates as compared with EAM. The reasons for these differences are unclear. However, it is clear that AAM have more advanced PCa when diagnosed. Several other reasons have been suggested and these include differences in treatments and health seeking behavior among the ethnic groups, cultural beliefs, environmental/lifestyle factors, dietary and genetic factors. In conclusion, there are multiple factors that impact prostate cancer outcome and that may be responsible for ethnic disparity. These factors are discussed in this chapter. PMID:19107447

  4. A novel genomic alteration of LSAMP associates with aggressive prostate cancer in African American men

    Directory of Open Access Journals (Sweden)

    Gyorgy Petrovics

    2015-12-01

    Full Text Available Evaluation of cancer genomes in global context is of great interest in light of changing ethnic distribution of the world population. We focused our study on men of African ancestry because of their disproportionately higher rate of prostate cancer (CaP incidence and mortality. We present a systematic whole genome analyses, revealing alterations that differentiate African American (AA and Caucasian American (CA CaP genomes. We discovered a recurrent deletion on chromosome 3q13.31 centering on the LSAMP locus that was prevalent in tumors from AA men (cumulative analyses of 435 patients: whole genome sequence, 14; FISH evaluations, 101; and SNP array, 320 patients. Notably, carriers of this deletion experienced more rapid disease progression. In contrast, PTEN and ERG common driver alterations in CaP were significantly lower in AA prostate tumors compared to prostate tumors from CA. Moreover, the frequency of inter-chromosomal rearrangements was significantly higher in AA than CA tumors. These findings reveal differentially distributed somatic mutations in CaP across ancestral groups, which have implications for precision medicine strategies.

  5. I Would Rather Just Go Through With It Than Be Called a Wussy: An Exploration of How a Group of Young South African Men Think and Talk About Suicide.

    Science.gov (United States)

    Meissner, Birte; Bantjes, Jason; Kagee, Ashraf

    2016-07-01

    Worldwide suicide is a deeply gendered phenomenon. In South Africa, approximately 80% of suicide completers are male. This study aimed to investigate how a group of young South African men understand and think about suicidal behavior. In-depth semistructured interviews and thematic analysis using a grounded theory approach revealed that this group of young South African men had permissive attitudes to suicide and viewed suicide as a morally defensible alternative in specific situations. They spoke of suicide as a goal-directed behavior that provides a means of regaining control, asserting power, communicating, and rendering oneself visible. From this perspective, suicide was understood as a brave act requiring strength and determination. These data have congruence with the Theory of Gender and Health, which proposes that constructions of masculinity may be implicated in the attitudes and beliefs young men in South Africa hold toward suicide. PMID:25631278

  6. Strong genetic admixture in the Altai at the Middle Bronze Age revealed by uniparental and ancestry informative markers.

    Science.gov (United States)

    Hollard, Clémence; Keyser, Christine; Giscard, Pierre-Henri; Tsagaan, Turbat; Bayarkhuu, Noost; Bemmann, Jan; Crubézy, Eric; Ludes, Bertrand

    2014-09-01

    The Altai Mountains have been a long-term boundary zone between the Eurasian Steppe populations and South and East Asian populations. To disentangle some of the historical population movements in this area, 14 ancient human specimens excavated in the westernmost part of the Mongolian Altai were studied. Thirteen of them were dated from the Middle to the End of the Bronze Age and one of them to the Eneolithic period. The environmental conditions encountered in this region led to the good preservation of DNA in the human remains. Therefore, a multi-markers approach was adopted for the genetic analysis of identity, ancestry and phenotype markers. Mitochondrial DNA analyses revealed that the ancient Altaians studied carried both Western (H, U, T) and Eastern (A, C, D) Eurasian lineages. In the same way, the patrilineal gene pool revealed the presence of different haplogroups (Q1a2a1-L54, R1a1a1b2-Z93 and C), probably marking different origins for the male paternal lineages. To go further in the search of the origin of these ancient specimens, phenotypical characters (i.e. hair and eye color) were determined. For this purpose, we adapted the HIrisPlex assay recently described to MALDI-TOF mass spectrometry. In addition, some ancestry informative markers were analyzed with this assay. The results revealed mixed phenotypes among this group confirming the probable admixed ancestry of the studied Altaian population at the Middle Bronze Age. The good results obtained from ancient DNA samples suggest that this approach might be relevant for forensic casework too. PMID:25016250

  7. Biogeografia de Portugal Continental

    OpenAIRE

    Costa, José C.; Aguiar, Carlos; Capelo, J.; Lousã, Mário; Neto, Carlos

    1998-01-01

    Apresentam-se alguns conceitos fundamentais usados em Biogeografia. Propõe-se uma tipologia biogeográfica para Portugal continental desenvolvida a partir dos trabalhos de S. Rivas-Martínez para a Península Ibérica, principalmente: RIVAS-MARTÍNEZ et al (1990). São enumeradas as unidades biogeográficas reconhecidas no território continental nacional e discutem-se os seus limites até ao nível de Superdistrito, bem como os critérios e fundamentos florísticos e fitossociológicos ...

  8. Trace element characteristics of mafic and ultramafic meta-igneous rocks from the 3.5 Ga. Warrawoona group: evidence for plume-lithosphere interaction beneath Archaean continental crust

    International Nuclear Information System (INIS)

    Full text: Magnesian- to Fe-rich tholeiitic basalts represent the dominant lithology in the Marble Bar Greenstone Belt, E-Pilbara Craton, and are locally associated with komatiitic basalts and rare komatiitic cumulates. Based on trace element characteristics, the extrusive and intrusive rocks from all three major stratigraphic units can be subdivided into LREE enriched and unfractionated to weakly LREE depleted groups. The former group is characterized by La/Smpm = 1.7-4.6, Gd/Ybpm = 1.23.2 and Nb/Thpm 0.1-0.5, while the latter rocks possess ratios of La/Smpm = 0.5-1.7, Gd/Ybpm = 0.8-1.9 and Nb/Thpm = 0.4-1.3. Nb/La -Nb/Th relationships in the LREE enriched samples indicate 7-28% contamination by crustal material similar in composition to Pilbara granitoids. LREE enrichment and strong negative HFSE anomalies, along with MgO = 2.2-22.0 wt% and SiO2 = 39.2-63.5 wt%, have been observed in numerous Archaean greenstone belts, and can be successfully modeled in this study by AFC processes. In contrast, strong HFSE depletion combined with unfractionated to slightly depleted LREE in rocks of the latter group require different processes. Melting of mantle material previously depleted by melt extraction, enrichment of LILE and LREE relative to the HFSE in an arc-like environment and HFSE fractionation as a result of garnet retention in the melting source cannot account for negative Nb, Ta, Ti, P and strong positive Pb anomalies. Introduction of small amounts of crustal material into a depleted or primitive mantle, as possibly indicated by Nb/Ta ratios between 12 and 18, also fails to reproduce the trace element abundances of the second group of rocks. Recycling of oceanic crust previously processed through a subduction zone (low Th/Nb, La/Nb) and sub-arc lithospheric mantle (high Th/Nb, La/Nb), and subsequent mixing into the Archaean mantle has been recently invoked by several workers (e.g. Kerrich et al., EPSL, 168, 101-115; 1999) to explain the origin of compositionally

  9. Zār Spirit Possession in Iran and African Countries: Group Distress, Culture-Bound Syndrome or Cultural Concept of Distress?

    OpenAIRE

    Fahimeh Mianji; Yousef Semnani

    2015-01-01

    Zār is the term used to describe a form of spirit possession common in northern African, eastern African, and some Middle-Eastern societies. Although these regions share some cultural similarities arising from their history of slavery, in these places, zār varies in prevalence, clinical characteristics, and social context. Based on a selective review of the literature, this paper looks at the place of zār spirit possession in both DSM-IV and DSM-V; it also examines how zār is manifested in Ir...

  10. Continental magnetic anomaly constraints on continental reconstruction

    Science.gov (United States)

    Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

    1985-01-01

    Crustal magnetic anomalies mapped by the MAGSAT satellite for North and South America, Europe, Africa, India, Australia and Antarctica and adjacent marine areas were adjusted to a common elevation of 400 km and differentially reduced to the radial pole of intensity 60,000 nT. These radially polarized anomalies are normalized for differential inclination, declination and intensity effects of the geomagnetic field, so that in principle they directly reflected the geometric and magnetic polarization attributes of sources which include regional petrologic variations of the crust and upper mantle, and crustal thickness and thermal perturbations. Continental anomalies demonstrate remarkably detailed correlation of regional magnetic sources across rifted margins when plotted on a reconstruction of Pangea. Accordingly, they suggest further fundamental constraints on the geologic evolution of the continents and their reconstructions.

  11. The African Diaspora: Mitochondrial DNA and the Atlantic Slave Trade

    Science.gov (United States)

    Salas, Antonio; Richards, Martin; Lareu, María-Victoria; Scozzari, Rosaria; Coppa, Alfredo; Torroni, Antonio; Macaulay, Vincent; Carracedo, Ángel

    2004-01-01

    Between the 15th and 19th centuries ad, the Atlantic slave trade resulted in the forced movement of ∼13 million people from Africa, mainly to the Americas. Only ∼11 million survived the passage, and many more died in the early years of captivity. We have studied 481 mitochondrial DNAs (mtDNAs) of recent African ancestry in the Americas and in Eurasia, in an attempt to trace them back to particular regions of Africa. Our results show that mtDNAs in America and Eurasia can, in many cases, be traced to broad geographical regions within Africa, largely in accordance with historical evidence, and raise the possibility that a greater resolution may be possible in the future. However, they also indicate that, at least for the moment, considerable caution is warranted when assessing claims to be able to trace the ancestry of particular lineages to a particular locality within modern-day Africa. PMID:14872407

  12. Impact of ancestry and body size on sonographic ulnar nerve dimensions

    International Nuclear Information System (INIS)

    Introduction: The purpose of this study was to investigate the impact that geographic ancestry and body size have on ultrasonographic measurements of the ulnar nerve size measured at the elbow. Materials and methods: We performed anthropometric measurements of body size and ultrasonographic measurements of the ulnar nerve at the elbow on 13 Vietnamese and 24 European participants. Regression analysis was used to determine the effect of body size and geographic ancestry on ulnar nerve size. Results: BMI had the greatest impact on ulnar nerve size. The short axis diameter was least resilient, and the long axis diameter was the most resilient to the effects of body size and geographic ancestry. Discussion: The long axis diameter has an apparent immunity to the influences of overall body size, arm size, or geographic ancestry and has the most potential as a sensitive discriminator between normal nerves and nerves affected by ulnar neuropathy at the elbow.

  13. The Dialectics of African Education and Western Discourses: Counter-Hegemonic Perspectives. Black Studies and Critical Thinking. Volume 21

    Science.gov (United States)

    Wright, Handel Kashope, Ed.; Abdi, Ali A., Ed.

    2012-01-01

    "The Dialectics of African Education and Western Discourses" addresses how continental Africans who have worked or are currently working in the Canadian academy address their dual legacy of African and Euro-American knowledge paradigms. Reflecting a range of approaches to hegemonic Euro-American paradigms that can be summarized as "appropriation,…

  14. Fast individual ancestry inference from DNA sequence data leveraging allele frequencies for multiple populations

    OpenAIRE

    Bansal, Vikas; Libiger, Ondrej

    2015-01-01

    Background Estimation of individual ancestry from genetic data is useful for the analysis of disease association studies, understanding human population history and interpreting personal genomic variation. New, computationally efficient methods are needed for ancestry inference that can effectively utilize existing information about allele frequencies associated with different human populations and can work directly with DNA sequence reads. Results We describe a fast method for estimating the...

  15. Amerind ancestry, socioeconomic status and the genetics of type 2 diabetes in a Colombian population.

    Directory of Open Access Journals (Sweden)

    Desmond D Campbell

    Full Text Available The "thrifty genotype" hypothesis proposes that the high prevalence of type 2 diabetes (T2D in Native Americans and admixed Latin Americans has a genetic basis and reflects an evolutionary adaptation to a past low calorie/high exercise lifestyle. However, identification of the gene variants underpinning this hypothesis remains elusive. Here we assessed the role of Native American ancestry, socioeconomic status (SES and 21 candidate gene loci in susceptibility to T2D in a sample of 876 T2D cases and 399 controls from Antioquia (Colombia. Although mean Native American ancestry is significantly higher in T2D cases than in controls (32% v 29%, this difference is confounded by the correlation of ancestry with SES, which is a stronger predictor of disease status. Nominally significant association (P1 was observed for markers selected from previous T2D genome-wide association studies, consistent with a role for Old World variants in susceptibility to T2D in Latin Americans. No association was found to the only known Native American-specific gene variant previously associated with T2D in a Mexican sample (rs9282541 in ABCA1. An admixture mapping scan with 1,536 ancestry informative markers (AIMs did not identify genome regions with significant deviation of ancestry in Antioquia. Exclusion analysis indicates that this scan rules out ~95% of the genome as harboring loci with ancestry risk ratios >1.22 (at P < 0.05.

  16. Resolving the ancestry of Austronesian-speaking populations.

    Science.gov (United States)

    Soares, Pedro A; Trejaut, Jean A; Rito, Teresa; Cavadas, Bruno; Hill, Catherine; Eng, Ken Khong; Mormina, Maru; Brandão, Andreia; Fraser, Ross M; Wang, Tse-Yi; Loo, Jun-Hun; Snell, Christopher; Ko, Tsang-Ming; Amorim, António; Pala, Maria; Macaulay, Vincent; Bulbeck, David; Wilson, James F; Gusmão, Leonor; Pereira, Luísa; Oppenheimer, Stephen; Lin, Marie; Richards, Martin B

    2016-03-01

    There are two very different interpretations of the prehistory of Island Southeast Asia (ISEA), with genetic evidence invoked in support of both. The "out-of-Taiwan" model proposes a major Late Holocene expansion of Neolithic Austronesian speakers from Taiwan. An alternative, proposing that Late Glacial/postglacial sea-level rises triggered largely autochthonous dispersals, accounts for some otherwise enigmatic genetic patterns, but fails to explain the Austronesian language dispersal. Combining mitochondrial DNA (mtDNA), Y-chromosome and genome-wide data, we performed the most comprehensive analysis of the region to date, obtaining highly consistent results across all three systems and allowing us to reconcile the models. We infer a primarily common ancestry for Taiwan/ISEA populations established before the Neolithic, but also detected clear signals of two minor Late Holocene migrations, probably representing Neolithic input from both Mainland Southeast Asia and South China, via Taiwan. This latter may therefore have mediated the Austronesian language dispersal, implying small-scale migration and language shift rather than large-scale expansion. PMID:26781090

  17. Another Continental Vulture Crisis

    NARCIS (Netherlands)

    Ogada, Darcy; Shaw, Phil; Beyers, Rene L.; Buij, Ralph; Murn, Campbell; Thiollay, Jean Marc; Beale, Colin M.; Holdo, Ricardo M.; Pomeroy, Derek; Baker, Neil; Krüger, Sonja C.; Botha, Andre; Virani, Munir Z.; Monadjem, Ara; Sinclair, Anthony R.E.

    2016-01-01

    Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30-year Pan-African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, econ

  18. Brazilian continental cretaceous

    Science.gov (United States)

    Petri, Setembrino; Campanha, Vilma A.

    1981-04-01

    Cretaceous deposits in Brazil are very well developed, chiefly in continental facies and in thick sequences. Sedimentation occurred essentially in rift-valleys inland and along the coast. Three different sequences can be distinguished: (1) a lower clastic non-marine section, (2) a middle evaporitic section, (3) an upper marine section with non-marine regressive lithosomes. Continental deposits have been laid down chiefly between the latest Jurassic and Albian. The lower lithostratigraphic unit is represented by red shales with occasional evaporites and fresh-water limestones, dated by ostracods. A series of thick sandstone lithosomes accumulated in the inland rift-valleys. In the coastal basins these sequences are often incompletely preserved. Uplift in the beginning of the Aptian produced a widespread unconformity. In many of the inland rift-valleys sedimentation ceased at that time. A later transgression penetrated far into northeastern Brazil, but shortly after continental sedimentation continued, with the deposition of fluvial sandstones which once covered large areas of the country and which have been preserved in many places. The continental Cretaceous sediments have been laid down in fluvial and lacustrine environments, under warm climatic conditions which were dry from time to time. The fossil record is fairly rich, including besides plants and invertebrates, also reptiles and fishes. As faulting tectonism was rather strong, chiefly during the beginning of the Cretaceous, intercalations of igneous rocks are frequent in some places. Irregular uplift and erosion caused sediments belonging to the remainder of this period to be preserved only in tectonic basins scattered across the country.

  19. Genome-wide scan of 29,141 African Americans finds no evidence of selection since admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; William J Blot; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W Ryan; Gapstur, Susan M

    2013-01-01

    We scanned through the genomes of 29,141 African Americans, searching for loci where the average proportion of African ancestry deviates significantly from the genome-wide average. We failed to find any genome-wide significant deviations, and conclude that any selection in African Americans since admixture is sufficiently weak that it falls below the threshold of our power to detect it using a large sample size. These results stand in contrast to the findings of a recent study of selection in...

  20. ON THE CHOICE ADDRESS FORMS: INTIMATE ADDRESS FORMS AS IN-GROUP IDENTITY MARKERS OF BLACK SOUTH AFRICANS IN 'INVICTUS' MOVIE

    OpenAIRE

    Prihantoro Prihantoro

    2012-01-01

    Invictus is a movie which is adapted from a true story of how the South African President, Nelson Mandela, tried to unite South Africa by supporting the national rugby team, Springbok, which used to be the symbol of Apartheid. His relation with other characters in this movie is reflected from the address forms and the choice is influenced by many aspects like social distance among the participants, age difference, formality scale etc. This paper focuses on the choice of address forms used amo...

  1. The use of the Revised Griffiths Development Scales in a group of 9 month–old South African babies / Jacquiline von Wielligh

    OpenAIRE

    Von Wielligh, Jacquiline

    2012-01-01

    The aim of this study was to determine the applicability of the Griffiths Development Scales ? Extended Revised (GMDS–ER) in a contemporary South Africa. This study explores the performance of South African babies aged 9 months as it relates to that of British babies (from the standardisation sample). Over the last few years, researchers have made a significant effort to address the need for more reliable and valid assessment measures for South Africa. The literature study shows r...

  2. Cancer and African Americans

    Science.gov (United States)

    ... Population Profiles > Black/African American > Cancer Cancer and African Americans African Americans have the highest mortality rate ... 65MB] At a glance – Top Cancer Sites for African Americans (2008-2012) Cancer Incidence Rates per 100, ...

  3. Genomic microsatellites identify shared Jewish ancestry intermediate between Middle Eastern and European populations

    Directory of Open Access Journals (Sweden)

    Hillel Jossi

    2009-12-01

    Full Text Available Abstract Background Genetic studies have often produced conflicting results on the question of whether distant Jewish populations in different geographic locations share greater genetic similarity to each other or instead, to nearby non-Jewish populations. We perform a genome-wide population-genetic study of Jewish populations, analyzing 678 autosomal microsatellite loci in 78 individuals from four Jewish groups together with similar data on 321 individuals from 12 non-Jewish Middle Eastern and European populations. Results We find that the Jewish populations show a high level of genetic similarity to each other, clustering together in several types of analysis of population structure. Further, Bayesian clustering, neighbor-joining trees, and multidimensional scaling place the Jewish populations as intermediate between the non-Jewish Middle Eastern and European populations. Conclusion These results support the view that the Jewish populations largely share a common Middle Eastern ancestry and that over their history they have undergone varying degrees of admixture with non-Jewish populations of European descent.

  4. Genetic evidence for a mitochondriate ancestry in the 'amitochondriate' flagellate Trimastix pyriformis.

    Directory of Open Access Journals (Sweden)

    Vladimir Hampl

    Full Text Available Most modern eukaryotes diverged from a common ancestor that contained the alpha-proteobacterial endosymbiont that gave rise to mitochondria. The 'amitochondriate' anaerobic protist parasites that have been studied to date, such as Giardia and Trichomonas harbor mitochondrion-related organelles, such as mitosomes or hydrogenosomes. Yet there is one remaining group of mitochondrion-lacking flagellates known as the Preaxostyla that could represent a primitive 'pre-mitochondrial' lineage of eukaryotes. To test this hypothesis, we conducted an expressed sequence tag (EST survey on the preaxostylid flagellate Trimastix pyriformis, a poorly-studied free-living anaerobe. Among the ESTs we detected 19 proteins that, in other eukaryotes, typically function in mitochondria, hydrogenosomes or mitosomes, 12 of which are found exclusively within these organelles. Interestingly, one of the proteins, aconitase, functions in the tricarboxylic acid cycle typical of aerobic mitochondria, whereas others, such as pyruvate:ferredoxin oxidoreductase and [FeFe] hydrogenase, are characteristic of anaerobic hydrogenosomes. Since Trimastix retains genetic evidence of a mitochondriate ancestry, we can now say definitively that all known living eukaryote lineages descend from a common ancestor that had mitochondria.

  5. Genetic evidence for a mitochondriate ancestry in the 'amitochondriate' flagellate Trimastix pyriformis.

    Science.gov (United States)

    Hampl, Vladimir; Silberman, Jeffrey D; Stechmann, Alexandra; Diaz-Triviño, Sara; Johnson, Patricia J; Roger, Andrew J

    2008-01-01

    Most modern eukaryotes diverged from a common ancestor that contained the alpha-proteobacterial endosymbiont that gave rise to mitochondria. The 'amitochondriate' anaerobic protist parasites that have been studied to date, such as Giardia and Trichomonas harbor mitochondrion-related organelles, such as mitosomes or hydrogenosomes. Yet there is one remaining group of mitochondrion-lacking flagellates known as the Preaxostyla that could represent a primitive 'pre-mitochondrial' lineage of eukaryotes. To test this hypothesis, we conducted an expressed sequence tag (EST) survey on the preaxostylid flagellate Trimastix pyriformis, a poorly-studied free-living anaerobe. Among the ESTs we detected 19 proteins that, in other eukaryotes, typically function in mitochondria, hydrogenosomes or mitosomes, 12 of which are found exclusively within these organelles. Interestingly, one of the proteins, aconitase, functions in the tricarboxylic acid cycle typical of aerobic mitochondria, whereas others, such as pyruvate:ferredoxin oxidoreductase and [FeFe] hydrogenase, are characteristic of anaerobic hydrogenosomes. Since Trimastix retains genetic evidence of a mitochondriate ancestry, we can now say definitively that all known living eukaryote lineages descend from a common ancestor that had mitochondria. PMID:18167542

  6. Genome-wide association study of age at menarche in African-American women

    OpenAIRE

    Demerath, Ellen W; Liu, Ching-Ti; Franceschini, Nora; Chen, Gary; Palmer, Julie R.; Smith, Erin N.; Chen, Christina T. L.; Ambrosone, Christine B.; Arnold, Alice M.; Bandera, Elisa V.; Berenson, Gerald S.; Bernstein, Leslie; Britton, Angela; Cappola, Anne R.; Carlson, Christopher S.

    2013-01-01

    African-American (AA) women have earlier menarche on average than women of European ancestry (EA), and earlier menarche is a risk factor for obesity and type 2 diabetes among other chronic diseases. Identification of common genetic variants associated with age at menarche has a potential value in pointing to the genetic pathways underlying chronic disease risk, yet comprehensive genome-wide studies of age at menarche are lacking for AA women. In this study, we tested the genome-wide associati...

  7. Phytogeography of African Commelinaceae

    Directory of Open Access Journals (Sweden)

    R. B. Faden

    1983-12-01

    Full Text Available Africa (including Madagascar has nearly twice as many species of Commelinaceae as any other continent (approximately 270 species, or about 40% of the total in the family. Of the 17 genera which are native, seven (Anthericopsis, Coleotrype, Palisota, Polyspatha, Pseudoparis, Stanfieldiella and  Triceratella are endemic, the highest percentage generic endemism of any continent. Within Africa gcneric diversity is slightly higher in western than in eastern tropical floras. Species richness, however, is greatest in eastern Africa, mainly due to a high diversity of species of Commelina and Aneilema. Africa shares more genera with Asia (nine than with any other continent. Only one African genus, Buforrestia, is neither endemic nor shared with Asia. Its western African/northeastern South American distribution is unique in the family. Besides Buforrestia, only five other genera of Commelinaceae (out of a total of 50 in the family, occur in both the Old and New Worlds. These genera.  Aneilema, Commelina, Floscopa, Murdannia and  Pollia are all very widespread in the Old World, occurring in Australia and Asia in addition to Africa (both continental and Madagascar. Madagascar is relatively poor in species (31. but these include the endemic Madagascan genus Pseudoparis, the sole African species of Rhopalephora, and the largest number of species of the Afro-Malagasy endemic genus Coleotrype. The high rate of generic endemism of Commelinaceae in Africa probably indicates that Africa was one of the ancient centres of diversity for the family. The high species diversity is more likely due to relatively recent radiations by genera pre-adapted to survival in non-forest habitats. The occurrence of only a small number of genera on both sides of the Atlantic suggests that the Commelinaceae have been evolving independently in the eastern and western hemispheres for a long period.

  8. Another Continental Vulture Crisis

    OpenAIRE

    Ogada, Darcy; Shaw, Phil; Beyers, Rene L.; Buij, Ralph; Murn, Campbell; Thiollay, Jean Marc; Beale, Colin M.; Holdo, Ricardo M.; Pomeroy, Derek; Baker, Neil; Krüger, Sonja C.; Botha, Andre; Virani, Munir Z.; Monadjem, Ara; Sinclair, Anthony R. E.

    2016-01-01

    Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30-year Pan-African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, economic, and human costs are already documented. Populations of eight species we assessed had declined by an average of 62%; seven had declined at a rate of 80% or more over three generations. Of these, ...

  9. Islands in a desert : breeding ecology of the African Reed Warbler Acrocephalus baeticatus in Namibia

    NARCIS (Netherlands)

    Eising, CM; Komdeur, J; Buys, J; Reemer, M; Richardson, DS; Richardson, David S.

    2001-01-01

    The continental African Reed Warbler Acrocephalus baeticatus, like its relative the Seychelles Warbler Acrocephalus sechellensis, breeds in isolated patches. We studied the mating system of the African Reed Warbler to see whether this species, like the Seychelles Warbler, shows co-operative breeding

  10. Ancestry Estimation in Forensic Anthropology: Geometric Morphometric versus Standard and Nonstandard Interlandmark Distances.

    Science.gov (United States)

    Katherine Spradley, M; Jantz, Richard L

    2016-07-01

    Standard cranial measurements are commonly used for ancestry estimation; however, 3D digitizers have made cranial landmark data collection and geometric morphometric (GM) analyses more popular within forensic anthropology. Yet there has been little focus on which data type works best. The goal of the present research is to test the discrimination ability of standard and nonstandard craniometric measurements and data derived from GM analysis. A total of 31 cranial landmarks were used to generate 465 interlandmark distances, including a subset of 20 commonly used measurements, and to generate principal component scores from procrustes coordinates. All were subjected to discriminant function analysis to ascertain which type of data performed best for ancestry estimation of American Black and White and Hispanic males and females. The nonstandard interlandmark distances generated the highest classification rates for females (90.5%) and males (88.2%). Using nonstandard interlandmark distances over more commonly used measurements leads to better ancestry estimates for our current population structure. PMID:27364267

  11. Characterization of mutants of the vitamin-D-binding protein/group specific component: GC aborigine (1A1) from Australian aborigines and South African blacks, and 2A9 from south Germany.

    Science.gov (United States)

    Kofler, A; Braun, A; Jenkins, T; Serjeantson, S W; Cleve, H

    1995-01-01

    The structure and organization of the human vitamin-D-binding protein gene (DBP, group-specific component, GC) have recently been determined. Each exon may now be amplified by the PCR method using oligonucleotide primers deduced from the intron sequences near their 5' ends and 3' ends. In this study we examined the anodal GC variants 1A1 and 2A9. Genomic DNA of the variant 1A1 was obtained from Australian Aborigines and from South African Bantu-speaking Blacks. Amplification and sequencing of exon 11 of 1A1 revealed a point mutation in codon 429 at the second position. It is remarkable that this mutation was found in the Australian 1A1 variant and in the African 1A1 variant, and raises the question whether the mutation in these two ethnic groups has a common origin. Genomic DNA of the 2A variant called 2A9 was obtained from South Germany and a point mutation also concerning position 429 in exon 11 was found. The nucleotide exchange in this case, however, was at the first position of the codon. The widely distributed genetic polymorphism of DBP/GC is located in exon 11 and is characterized by substitution at amino acid positions 416 and 420. Variant 1A1 is due to a second site mutation of the allele GC*1F; variant 2A9 is due to a mutation in the GC*2 allele. PMID:7725672

  12. African dance

    OpenAIRE

    Mumberson, Stephen

    2012-01-01

    The RE Open will be shown at the Mall Gallery London and the international section was judged by major practitioners and educators, print dealers and collectors, President of RE and Keeper of the Ashmolean Museum Dr Bren Unwin, John Purcell, Deborah Roslund, Colin Harrison, Dave Ferry, and Mark Hampson. Piece selected "African Dance" print.

  13. Regional, Continental, and Global Mobility to an Emerging Economy: The Case of South Africa

    Science.gov (United States)

    Lee, Jenny J.; Sehoole, Chika

    2015-01-01

    This study examined mobility within the understudied region of southern Africa and particularly, the factors that drive and shape educational migration toward South Africa as a regional, continental, and global destination. Based on a survey administered to international students across seven South African universities, the findings revealed…

  14. Islands in a desert: breeding ecology of the African Reed Warbler Acrocephalus baeticatus in Namibia

    OpenAIRE

    Eising, CM; Komdeur, J.; Buys, J.; Reemer, M.; Richardson, DS; Richardson, David S.

    2001-01-01

    The continental African Reed Warbler Acrocephalus baeticatus, like its relative the Seychelles Warbler Acrocephalus sechellensis, breeds in isolated patches. We studied the mating system of the African Reed Warbler to see whether this species, like the Seychelles Warbler, shows co-operative breeding. The African Reed Warbler is not polygynous. The majority breed monogamously (88%, n = 65), however in 12% of the territories three adult unrelated birds (mostly males) were observed participating...

  15. Genome-wide association of anthropometric traits in African- and African-derived populations.

    Science.gov (United States)

    Kang, Sun J; Chiang, Charleston W K; Palmer, Cameron D; Tayo, Bamidele O; Lettre, Guillaume; Butler, Johannah L; Hackett, Rachel; Adeyemo, Adebowale A; Guiducci, Candace; Berzins, Ilze; Nguyen, Thutrang T; Feng, Tao; Luke, Amy; Shriner, Daniel; Ardlie, Kristin; Rotimi, Charles; Wilks, Rainford; Forrester, Terrence; McKenzie, Colin A; Lyon, Helen N; Cooper, Richard S; Zhu, Xiaofeng; Hirschhorn, Joel N

    2010-07-01

    Genome-wide association (GWA) studies have identified common variants that are associated with a variety of traits and diseases, but most studies have been performed in European-derived populations. Here, we describe the first genome-wide analyses of imputed genotype and copy number variants (CNVs) for anthropometric measures in African-derived populations: 1188 Nigerians from Igbo-Ora and Ibadan, Nigeria, and 743 African-Americans from Maywood, IL. To improve the reach of our study, we used imputation to estimate genotypes at approximately 2.1 million single-nucleotide polymorphisms (SNPs) and also tested CNVs for association. No SNPs or common CNVs reached a genome-wide significance level for association with height or body mass index (BMI), and the best signals from a meta-analysis of the two cohorts did not replicate in approximately 3700 African-Americans and Jamaicans. However, several loci previously confirmed in European populations showed evidence of replication in our GWA panel of African-derived populations, including variants near IHH and DLEU7 for height and MC4R for BMI. Analysis of global burden of rare CNVs suggested that lean individuals possess greater total burden of CNVs, but this finding was not supported in an independent European population. Our results suggest that there are not multiple loci with strong effects on anthropometric traits in African-derived populations and that sample sizes comparable to those needed in European GWA studies will be required to identify replicable associations. Meta-analysis of this data set with additional studies in African-ancestry populations will be helpful to improve power to detect novel associations. PMID:20400458

  16. Southeast continental shelf studies

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, D.W.

    1979-02-12

    Research efforts on the southeast continental shelf currently describe the manner in which fluctuations in Gulf Stream motion influence biological and chemical processes. Current meter arrays are maintained in the Georgia Bight and in Onslow Bay to describe general circulation patterns and to identify forcing functions. biological studies describe processes affecting temporal and spatial variations on the shelf and have attempted to track the biological history of intruded Gulf Stream water masses. Chemical studies examine the influence of both physical and biological variables on the distribution and fate of trace elements. The current state of knowledge is reviewed, the hypotheses developed and are described, a rationale for testing these hypotheses is given. 1 figure, 1 table.

  17. The continental lithosphere

    DEFF Research Database (Denmark)

    Artemieva, Irina

    2009-01-01

    The goal of the present study is to extract non-thermal signal from seismic tomography models in order to distinguish compositional variations in the continental lithosphere and to examine if geochemical and petrologic constraints on global-scale compositional variations in the mantle are...... consistent with modern geophysical data. In the lithospheric mantle of the continents, seismic velocity variations of a non-thermal origin (calculated from global Vs seismic tomography data [Grand S.P., 2002. Mantle shear-wave tomography and the fate of subducted slabs. Philosophical Transactions of the...... and evolution of Precambrian lithosphere: A global study. Journal of Geophysical Research 106, 16387–16414.] show strong correlation with tectono-thermal ages and with regional variations in lithospheric thickness constrained by surface heat flow data and seismic velocities. In agreement with xenolith...

  18. Updated checklist of marine fishes (Chordata: Craniata from Portugal and the proposed extension of the Portuguese continental shelf

    Directory of Open Access Journals (Sweden)

    Miguel Carneiro

    2014-02-01

    Full Text Available The study of the Portuguese marine ichthyofauna has a long historical tradition, rooted back in the 18th Century. Here we present an annotated checklist of the marine fishes from Portuguese waters, including the area encompassed by the proposed extension of the Portuguese continental shelf and the Economic Exclusive Zone (EEZ. The list is based on historical literature records and taxon occurrence data obtained from natural history collections, together with new revisions and occurrences. It comprises a total of 1191 species, distributed among 3 superclasses, 4 classes, 42 orders, 212 families and 617 genera. If considering only the EEZ and present territorial waters, this list represents an increase of 230 species (27.8% and of 238 species (29.0%, when compared to the information available in FishBase (2012 and in the last checklist of marine and estuarine fishes of Portugal (1993, respectively. The order Perciformes shows the highest diversity, with 54 families, 162 genera and 299 species. Stomiidae (80 species, Myctophidae (71 species and Macrouridae (37 species are the richest families. From the listed species, 734 are present off mainland Portugal, 857 off the Azores and 766 off Madeira. Within the limits of the examined area, three species are reported for the first time in mainland Portugal and twenty-nine records are identified as doubtful. A total of 133 species have been recorded from the extended Portuguese continental shelf (2 off mainland Portugal, 117 off the Azores and 14 off Madeira, two of which are common to the Azores and Madeira extensions. Biogeographically, the Atlantic group is the most important (548 species – 46.01%, followed by the Lusitanian group (256 species – 21.49%, the African group (71 species – 5.96%, the Boreal group (34 species – 2.85%, the Mediterranean group (31 species – 2.60%, the Macaronesian group (21 species – 1.76%, the Atlantic/African group (19 species – 1.60% and the Mediterranean/African

  19. Variation in Rural African Gut Microbiota Is Strongly Correlated with Colonization by Entamoeba and Subsistence.

    Science.gov (United States)

    Morton, Elise R; Lynch, Joshua; Froment, Alain; Lafosse, Sophie; Heyer, Evelyne; Przeworski, Molly; Blekhman, Ran; Ségurel, Laure

    2015-11-01

    The human gut microbiota is impacted by host nutrition and health status and therefore represents a potentially adaptive phenotype influenced by metabolic and immune constraints. Previous studies contrasting rural populations in developing countries to urban industrialized ones have shown that industrialization is strongly correlated with patterns in human gut microbiota; however, we know little about the relative contribution of factors such as climate, diet, medicine, hygiene practices, host genetics, and parasitism. Here, we focus on fine-scale comparisons of African rural populations in order to (i) contrast the gut microbiota of populations inhabiting similar environments but having different traditional subsistence modes and either shared or distinct genetic ancestry, and (ii) examine the relationship between gut parasites and bacterial communities. Characterizing the fecal microbiota of Pygmy hunter-gatherers as well as Bantu individuals from both farming and fishing populations in Southwest Cameroon, we found that the gut parasite Entamoeba is significantly correlated with microbiome composition and diversity. We show that across populations, colonization by this protozoa can be predicted with 79% accuracy based on the composition of an individual's gut microbiota, and that several of the taxa most important for distinguishing Entamoeba absence or presence are signature taxa for autoimmune disorders. We also found gut communities to vary significantly with subsistence mode, notably with some taxa previously shown to be enriched in other hunter-gatherers groups (in Tanzania and Peru) also discriminating hunter-gatherers from neighboring farming or fishing populations in Cameroon. PMID:26619199

  20. Variation in Rural African Gut Microbiota Is Strongly Correlated with Colonization by Entamoeba and Subsistence.

    Directory of Open Access Journals (Sweden)

    Elise R Morton

    2015-11-01

    Full Text Available The human gut microbiota is impacted by host nutrition and health status and therefore represents a potentially adaptive phenotype influenced by metabolic and immune constraints. Previous studies contrasting rural populations in developing countries to urban industrialized ones have shown that industrialization is strongly correlated with patterns in human gut microbiota; however, we know little about the relative contribution of factors such as climate, diet, medicine, hygiene practices, host genetics, and parasitism. Here, we focus on fine-scale comparisons of African rural populations in order to (i contrast the gut microbiota of populations inhabiting similar environments but having different traditional subsistence modes and either shared or distinct genetic ancestry, and (ii examine the relationship between gut parasites and bacterial communities. Characterizing the fecal microbiota of Pygmy hunter-gatherers as well as Bantu individuals from both farming and fishing populations in Southwest Cameroon, we found that the gut parasite Entamoeba is significantly correlated with microbiome composition and diversity. We show that across populations, colonization by this protozoa can be predicted with 79% accuracy based on the composition of an individual's gut microbiota, and that several of the taxa most important for distinguishing Entamoeba absence or presence are signature taxa for autoimmune disorders. We also found gut communities to vary significantly with subsistence mode, notably with some taxa previously shown to be enriched in other hunter-gatherers groups (in Tanzania and Peru also discriminating hunter-gatherers from neighboring farming or fishing populations in Cameroon.

  1. Deciphering and dating the red panda's ancestry and early adaptive radiation of Musteloidea.

    Science.gov (United States)

    Sato, Jun J; Wolsan, Mieczyslaw; Minami, Shinji; Hosoda, Tetsuji; Sinaga, Martua H; Hiyama, Kozue; Yamaguchi, Yasunori; Suzuki, Hitoshi

    2009-12-01

    Few species have been of more disputed affinities than the red or lesser panda (Ailurus fulgens), an endangered endemic Southeast Asian vegetarian member of the placental mammalian order Carnivora. This peculiar carnivoran has mostly been classified with raccoons (Procyonidae) or bears (Ursidae), grouped with the giant panda (Ailuropoda melanoleuca) in their own family, or considered a separate lineage of equivocal ancestry. Recent molecular studies have indicated a close affinity of the red panda to a clade of procyonids and mustelids (weasels, otters, martens, badgers, and allies), but have failed to unambiguously resolve the position of this species relative to mephitids (skunks and stink badgers). We examined the relationship of the red panda to other extant species of the carnivoran suborder Caniformia using a set of concatenated approximately 5.5-kb sequences from protein-coding exons of five nuclear genes. Bayesian, maximum likelihood, and parsimony phylogenetic analyses strongly supported the red panda as the closest living relative of a clade containing Procyonidae and Mustelidae to the exclusion of Mephitidae. These three families together with the red panda (which is classified here as a single extant species of a distinct family, Ailuridae) compose the superfamily Musteloidea, a clade strongly supported by all our phylogenetic analyses as sister to the monophyletic Pinnipedia (seals, sea lions, walruses). The approximately unbiased, Kishino-Hasegawa, and Templeton topology tests rejected (Pfossil evidence that extends the early adaptive radiation of the total clade of musteloids to the Eocene-Oligocene transition and also suggests Asia as a center of this radiation. PMID:19699810

  2. Rapid phenotypic evolution during incipient speciation in a continental avian radiation

    Science.gov (United States)

    Campagna, Leonardo; Benites, Pilar; Lougheed, Stephen C.; Lijtmaer, Darío A.; Di Giacomo, Adrián S.; Eaton, Muir D.; Tubaro, Pablo L.

    2012-01-01

    Adaptive radiations have helped shape how we view animal speciation, particularly classic examples such as Darwin's finches, Hawaiian fruitflies and African Great Lakes cichlids. These ‘island’ radiations are comparatively recent, making them particularly interesting because the mechanisms that caused diversification are still in motion. Here, we identify a new case of a recent bird radiation within a continentally distributed species group; the capuchino seedeaters comprise 11 Sporophila species originally described on the basis of differences in plumage colour and pattern in adult males. We use molecular data together with analyses of male plumage and vocalizations to understand species limits of the group. We find marked phenotypic variation despite lack of mitochondrial DNA monophyly and few differences in other putatively neutral nuclear markers. This finding is consistent with the group having undergone a recent radiation beginning in the Pleistocene, leaving genetic signatures of incomplete lineage sorting, introgressive hybridization and demographic expansions. We argue that this apparent uncoupling between neutral DNA homogeneity and phenotypic diversity is expected for a recent group within the framework of coalescent theory. Finally, we discuss how the ecology of open habitats in South America during the Pleistocene could have helped promote this unique and ongoing radiation. PMID:22130601

  3. Current and future nitrous oxide emissions from African agriculture

    NARCIS (Netherlands)

    Hickman, J.E.; Havlikova, M.; Kroeze, C.; Palm, C.A.

    2011-01-01

    Most emission estimates of the greenhouse gas nitrous oxide (N2O) from African agriculture at a continental scale are based on emission factors, such as those developed by the IPCC Guidelines. Here we present estimates from Africa from the EDGAR database, which is derived from the IPCC emission fact

  4. 75 FR 11940 - Office of the Chief Human Capital Officer; Information Collection; Ancestry and Ethnicity Data...

    Science.gov (United States)

    2010-03-12

    ... NATIONAL INTELLIGENCE Office of the Chief Human Capital Officer; Information Collection; Ancestry and... the Chief Human Capital Officer, ODNI, at Washington, DC 20511, or call 703-275-3369. Please cite... submitted on or before April 12, 2010. FOR FURTHER INFORMATION CONTACT: The Office of the Chief...

  5. Diversity among African pygmies.

    Directory of Open Access Journals (Sweden)

    Fernando V Ramírez Rozzi

    Full Text Available Although dissimilarities in cranial and post-cranial morphology among African pygmies groups have been recognized, comparative studies on skull morphology usually pull all pygmies together assuming that morphological characters are similar among them and different with respect to other populations. The main aim of this study is to compare cranial morphology between African pygmies and non-pygmies populations from Equatorial Africa derived from both the Eastern and the Western regions in order to test if the greatest morphological difference is obtained in the comparison between pygmies and non-pygmies. Thirty three-dimensional (3D landmarks registered with Microscribe in four cranial samples (Western and Eastern pygmies and non-pygmies were obtained. Multivariate analysis (generalized Procrustes analysis, Mahalanobis distances, multivariate regression and complementary dimensions of size were evaluated with ANOVA and post hoc LSD. Results suggest that important cranial shape differentiation does occur between pygmies and non-pygmies but also between Eastern and Western populations and that size changes and allometries do not affect similarly Eastern and Western pygmies. Therefore, our findings raise serious doubt about the fact to consider African pygmies as a homogenous group in studies on skull morphology. Differences in cranial morphology among pygmies would suggest differentiation after divergence. Although not directly related to skull differentiation, the diversity among pygmies would probably suggest that the process responsible for reduced stature occurred after the split of the ancestors of modern Eastern and Western pygmies.

  6. Obesity and African Americans

    Science.gov (United States)

    ... Data > Minority Population Profiles > Black/African American > Obesity Obesity and African Americans African American women have the ... ss6304.pdf [PDF | 3.38MB] HEALTH IMPACT OF OBESITY More than 80 percent of people with type ...

  7. The Role of Regional Economic and Political Groups in the Globalization Process: A Case Study of the Economic Community of West African States (ECOWAS (1982-2002

    Directory of Open Access Journals (Sweden)

    Azalahu F. Akwara

    2013-12-01

    Full Text Available A regional integration by its very nature integrates its members into an economic union and acts as a bloc on matters affecting its members vis-a-vis other regional blocs and non members. Its hegemonic nature of hedging its members against all forms of exploitation and intimidation by other regional blocs and non-members and its desire to stem the tide of trade diversion, and to create and foster intra-union flow of trade, factors and investment at the exclusion of non-members and other regional blocs run contradictory to the aims and objectives of the globalization process which is the integration of the world economy through the breaking down of trade and investment barriers worldwide. Given these contradictory objectives of the regional blocs and the globalization process, this study examines the roles of the ECOWAS as an agent in the globalization process in the West African sub-region, its constraints, and solutions to the problems.

  8. Dynamics of continental accretion.

    Science.gov (United States)

    Moresi, L; Betts, P G; Miller, M S; Cayley, R A

    2014-04-10

    Subduction zones become congested when they try to consume buoyant, exotic crust. The accretionary mountain belts (orogens) that form at these convergent plate margins have been the principal sites of lateral continental growth through Earth's history. Modern examples of accretionary margins are the North American Cordilleras and southwest Pacific subduction zones. The geologic record contains abundant accretionary orogens, such as the Tasmanides, along the eastern margin of the supercontinent Gondwana, and the Altaïdes, which formed on the southern margin of Laurasia. In modern and ancient examples of long-lived accretionary orogens, the overriding plate is subjected to episodes of crustal extension and back-arc basin development, often related to subduction rollback and transient episodes of orogenesis and crustal shortening, coincident with accretion of exotic crust. Here we present three-dimensional dynamic models that show how accretionary margins evolve from the initial collision, through a period of plate margin instability, to re-establishment of a stable convergent margin. The models illustrate how significant curvature of the orogenic system develops, as well as the mechanism for tectonic escape of the back-arc region. The complexity of the morphology and the evolution of the system are caused by lateral rollback of a tightly arcuate trench migrating parallel to the plate boundary and orthogonally to the convergence direction. We find geological and geophysical evidence for this process in the Tasmanides of eastern Australia, and infer that this is a recurrent and global phenomenon. PMID:24670638

  9. Ancestry informative markers and complete blood count parameters in Brazilian blood donors Marcadores informativos de ancestralidade e parâmetros no hemograma de doadores de sangue brasileiros

    Directory of Open Access Journals (Sweden)

    Gabriela E. S. Felix

    2010-01-01

    Full Text Available A complete blood count is very useful in clinical diagnoses when reference ranges are well established for the population. Complete blood counts and allele frequencies of Ancestry Informative Markers (AIMs were analyzed in Brazilians with the aim of characterizing the hematological values of an admixed population. Positive associations were observed between gender and neutrophils, monocytes, eosinophils, erythrocytes, hemoglobin, hematocrit, MCV, MCHC and platelet counts. No significant differences were found for age, alcohol consumption, educational status, ethnicity, smoking in respect to the complete blood count values. In general, men had higher red blood cell values, while women had higher values for white blood cells and platelets. The study of the population was highly heterogeneous with mean proportions (± SE of African, European and Amerindian ancestry being 49.0 ± 3.0%, 44.0 ± 9.0% and 7.0 ± 9.0%, respectively. Amerindian ancestry showed limited contribution to the makeup of the population, but estimated ancestral proportions were statistically significant (r = 0.9838; PO hemograma é muito útil no diagnóstico quando o intervalo de referência é adequadamente estabelecido para população. Com o objetivo de verificar os valores hematológicos em população heterogênea foi analisado o hemograma e frequências alélica de marcadores informativos de ancestralidade de brasileiros. Foi observada associação positiva entre sexo e os valores de neutrófilos, monócitos, eosinófilos, eritrócitos, hemoglobina, hematócrito, MCV, MCHC e plaquetas (IC 95%; P0,05. Os homens apresentaram valores maiores no eritrograma, enquanto no leucograma e plaquetograma foram as mulheres. Foi observado também que a população é altamente heterogênea e as médias proporcionais (±DP de ancestralidade Africana, Europeia e Ameríndia estimada foram: 49,0 ± 3,0 %, 44,0 ± 9,0% e 7,0 ± 9,0%, respectivamente. A contribuição ancestral ameríndia se

  10. Oral Cancer in African Americans: Addressing Health Disparities

    Science.gov (United States)

    Dodd, Virginia J.; Watson, Jennifer M.; Choi, Youjin; Tomar, Scott L.; Logan, Henrietta L.

    2008-01-01

    Objectives: To explore factors underlying African Americans' perceptions of oral cancer and the oral cancer exam. Study findings were used to guide development of oral cancer messages designed to increase oral cancer exams among African Americans. Methods: Focus groups were conducted to understand African Americans' attitudes and expectations…

  11. West Africa - A Safe Haven for Frogs? A Sub-Continental Assessment of the Chytrid Fungus (Batrachochytrium dendrobatidis)

    OpenAIRE

    Penner, Johannes; Adum, Gilbert B.; McElroy, Matthew T.; Doherty-Bone, Thomas; Hirschfeld, Mareike; Sandberger, Laura; Weldon, Ché; Cunningham, Andrew A; Ohst, Torsten; Wombwell, Emma; Portik, Daniel M.; Reid, Duncan; Hillers, Annika; Ofori-Boateng, Caleb; Oduro, William

    2013-01-01

    A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd). While Bd has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West African amphibians (one caecilian and 61 anuran species) for the presence of Bd. The samples originated from seven West African countries - Bénin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a variety of habi...

  12. West Africa – a safe haven for frogs? A sub–continental assessment of the Chytrid Fungus (Batrachochytrium dendrobatidis)

    OpenAIRE

    Penner, Johannes; Weldon, Ché; Adum, Gilbert B.; McElroy, Matthew T.; Doherty-Bone, Thomas

    2013-01-01

    A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd). While Bd has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West African amphibians (one caecilian and 61 anuran species) for the presence of Bd. The samples originated from seven West African countries - Be´nin, Burkina Faso, Coˆ te d’Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a var...

  13. Continental United States Hurricane Strikes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Continental U.S. Hurricane Strikes Poster is our most popular poster which is updated annually. The poster includes all hurricanes that affected the U.S. since...

  14. Highly discrepant proportions of female and male Scandinavian and British Isles ancestry within the isolated population of the Faroe Islands

    DEFF Research Database (Denmark)

    Als, Thomas D; Jorgensen, Tove H; Børglum, Anders D;

    2006-01-01

    frequency-based admixture approach taking private haplotypes into account by the use of phylogenetic information. While previous studies have suggested an excess of Scandinavian ancestry among the male settlers of the Faroe Islands, the current study indicates an excess of British Isles ancestry among the...... female settlers of the Faroe Islands. Compared to other admixed populations of the North Atlantic region, the population of the Faroe Islands appears to have the highest level of asymmetry in Scandinavian vs British Isles ancestry proportions among female and male settlers of the archipelago....

  15. Deep Continental Crustal Earthquakes and Lithospheric Structure: A Global Synthesis

    Science.gov (United States)

    Devlin, S.; Isacks, B. L.

    2007-12-01

    The distribution of earthquake depths within the continental crust defines the seismogenic thickness (TS), over which at least some part of crustal deformation is accommodated by rapid release of stored elastic strains. Intraplate continental seismicity is often thought to be restricted to the upper crust where TS is within the range of 15 to 20 km. This appears consistent with a lithospheric strength profile involving a weak, ductile lower crust located beneath a stronger, brittle upper crust. With the assumption of a strong uppermost mantle lid, this is often referred to the Jelly Sandwich model of lithosphere rheology. Studies in many places, however, document lower crustal earthquakes beneath continents in apparent disagreement with the model. We explore this and related issues through a survey of where and in what tectonic settings deep intraplate earthquakes are well documented in the continental crust. TS reaches Moho depth in many intraplate regions \\--- Sierra Nevada, Colorado Plateau, East African and Baikal Rift Systems, North Island New Zealand, Tien Shan, and the Andean and Alpine forelands. A review of possible deformation mechanisms which could control continental earthquake depth and facilitate seismicity beneath the brittle-ductile transition suggests that the influence of fluids is the only mechanism capable of encouraging earthquake occurrence throughout the continental crust at any tectonic setting. Surface derived fluids can induce pore fluid pressure changes to depths of 25 km and melt-reactions can induce earthquakes at depths throughout continental crust. On a global scale, fluid-enhanced embrittlement is not limited by depth or tectonic environment. We find that deep crustal earthquakes occur where the lithosphere is in a transitional state between primarily stable (e.g., shields) and highly deformed (e.g., U.S. Basin and Range or Southern California). Observations of relative intensity of tectonic deformation and regional percent strain

  16. -induced continental warming

    Science.gov (United States)

    Kamae, Youichi; Watanabe, Masahiro; Kimoto, Masahide; Shiogama, Hideo

    2014-11-01

    In this the second of a two-part study, we examine the physical mechanisms responsible for the increasing contrast of the land-sea surface air temperature (SAT) in summertime over the Far East, as observed in recent decades and revealed in future climate projections obtained from a series of transient warming and sensitivity experiments conducted under the umbrella of the Coupled Model Intercomparison Project phase 5. On a global perspective, a strengthening of land-sea SAT contrast in the transient warming simulations of coupled atmosphere-ocean general circulation models is attributed to an increase in sea surface temperature (SST). However, in boreal summer, the strengthened contrast over the Far East is reproduced only by increasing atmospheric CO2 concentration. In response to SST increase alone, the tropospheric warming over the interior of the mid- to high-latitude continents including Eurasia are weaker than those over the surrounding oceans, leading to a weakening of the land-sea SAT contrast over the Far East. Thus, the increasing contrast and associated change in atmospheric circulation over East Asia is explained by CO2-induced continental warming. The degree of strengthening of the land-sea SAT contrast varies in different transient warming scenarios, but is reproduced through a combination of the CO2-induced positive and SST-induced negative contributions to the land-sea contrast. These results imply that changes of climate patterns over the land-ocean boundary regions are sensitive to future scenarios of CO2 concentration pathways including extreme cases.

  17. Human cranial vault thickness in a contemporary sample of 1097 autopsy cases: relation to body weight, stature, age, sex and ancestry.

    Science.gov (United States)

    De Boer, H H Hans; Van der Merwe, A E Lida; Soerdjbalie-Maikoe, V Vidija

    2016-09-01

    The relation between human cranial vault thickness (CVT) and various elements of the physical anthropological biological profile is subject of ongoing discussion. Some results seem to indicate no correlation between CVT and the biological profile of the individual, whereas other results suggest that CVT measurements might be useful for identification purposes. This study assesses the correlation between CVT and body weight, stature, age, sex, and ancestry by reviewing data of 1097 forensic autopsies performed at the Netherlands Forensic Institute (NFI). In subadults (younger than 19 years of age at the time of death), all frontal, temporal, and occipital CVT measurements correlated moderately to strongly with indicators of growth (body weight, stature, and age). Neither sex nor ancestry correlated significantly with cranial thickness. In adults, body weight correlated with all CVT measurements. No meaningful correlation was found between CVT and stature or age. Females showed to have thicker frontal bones, and the occipital region was thicker in the Negroid subsample. All correlation in the adult group was weak, with the distribution of cranial thickness overlapping for a great deal between the groups. Based on these results, it was concluded that CVT generally cannot be used as an indicator for any part of the biological profile. PMID:26914798

  18. Ancestry and diversity of the HMG box superfamily

    OpenAIRE

    Laudet, V; Stehelin, D.; Clevers, J.C.

    1993-01-01

    The HMG box is a novel type of DNA-binding domain found in a diverse group of proteins. The HMG box superfamily comprises a.o. the High Mobility Group proteins HMG1 and HMG2, the nucleolar transcription factor UBF, the lymphoid transcription factors TCF-1 and LEF-1, the fungal mating-type genes mat-Mc and MATA1, and the mammalian sex-determining gene SRY. The superfamily dates back to at least 1,000 million years ago, as its members appear in animals, plants and yeast. Alignment of all known ...

  19. African diatom palaeoecology and biostratigraphy

    Science.gov (United States)

    Gasse, F.; Fourtanier, E.

    This paper illustrates the different types of information which can be deduced from African diatoms studies. The first section is devoted to the reconstruction of palaeoenvironments. The accuracy of ecological data (estimates of ecological variables e.g. types of habitats, water chemistry…) depends on the times scale and on the spatial scale considered: short-term environments in a given waterbody, environmental evolution during individual humid episodes considered locally or regionally, long-term changes in diatom flora induced by major climatic tendencies at a regional or continental scale. One then summarizes our present state of knowledge in diatom biostratigraphy in Africa. Several centric taxa, belonging to the genera Aulacoseira, Mesodictyon, Cyclotella, Stephanodiscus and Cyclostephanos appear to have limited stratigraphical ranges and to be good chronological markers.

  20. Ancestry informative markers and complete blood count parameters in Brazilian blood donors

    OpenAIRE

    Gabriela E. S. Felix; Kiyoko Abe-Sandes; Taísa M. Bonfim; Maria T. Bendicho; Patrícia Cisneiros; Rosalina Guedes; Cláudio J. F. Brandão; Alex J. L. Torres; Carlos Brites; Eduardo M. Netto; Roberto Meyer; Songeli M. Freire

    2010-01-01

    A complete blood count is very useful in clinical diagnoses when reference ranges are well established for the population. Complete blood counts and allele frequencies of Ancestry Informative Markers (AIMs) were analyzed in Brazilians with the aim of characterizing the hematological values of an admixed population. Positive associations were observed between gender and neutrophils, monocytes, eosinophils, erythrocytes, hemoglobin, hematocrit, MCV, MCHC and platelet counts. No significant diff...

  1. Inferring geographic coordinates of origin for Europeans using small panels of ancestry informative markers.

    Directory of Open Access Journals (Sweden)

    Petros Drineas

    Full Text Available Recent large-scale studies of European populations have demonstrated the existence of population genetic structure within Europe and the potential to accurately infer individual ancestry when information from hundreds of thousands of genetic markers is used. In fact, when genomewide genetic variation of European populations is projected down to a two-dimensional Principal Components Analysis plot, a surprising correlation with actual geographic coordinates of self-reported ancestry has been reported. This substructure can hamper the search of susceptibility genes for common complex disorders leading to spurious correlations. The identification of genetic markers that can correct for population stratification becomes therefore of paramount importance. Analyzing 1,200 individuals from 11 populations genotyped for more than 500,000 SNPs (Population Reference Sample, we present a systematic exploration of the extent to which geographic coordinates of origin within Europe can be predicted, with small panels of SNPs. Markers are selected to correlate with the top principal components of the dataset, as we have previously demonstrated. Performing thorough cross-validation experiments we show that it is indeed possible to predict individual ancestry within Europe down to a few hundred kilometers from actual individual origin, using information from carefully selected panels of 500 or 1,000 SNPs. Furthermore, we show that these panels can be used to correctly assign the HapMap Phase 3 European populations to their geographic origin. The SNPs that we propose can prove extremely useful in a variety of different settings, such as stratification correction or genetic ancestry testing, and the study of the history of European populations.

  2. Common Ancestry of Borrelia burgdorferi Sensu Lato Strains from North America and Europe

    OpenAIRE

    Postic, D; Ras, N. Marti; Lane, R S; Humair, P.-F.; Wittenbrink, M. M.; Baranton, G

    1999-01-01

    Ten atypical European Borrelia burgdorferi sensu lato (Borrelia spp.) strains were genetically characterized, and the diversity was compared to that encountered among related Borrelia spp. from North America. Phylogenetic analyses of a limited region of the genome and of the whole genome extend existing knowledge about borrelial diversity reported earlier in Europe and the United States. Our results accord with the evidence that North American and European strains may have a common ancestry.

  3. Clines of nuclear DNA markers suggest a largely Neolithic ancestry of the European gene pool

    OpenAIRE

    Chikhi, Lounès; Destro-Bisol, Giovanni; Bertorelle, Giorgio; Pascali, Vincenzo; Barbujani, Guido

    1998-01-01

    Comparisons between archaeological findings and allele frequencies at protein loci suggest that most genes of current Europeans descend from populations that have been expanding in Europe in the last 10,000 years, in the Neolithic period. Recent mitochondrial data have been interpreted as indicating a much older, Paleolithic ancestry. In a spatial autocorrelation study at seven hypervariable loci in Europe (four microsatellites, two larger, tandem-repeat loci, and a sequence polymorphism) bro...

  4. Bioenergetics of Continental Serpentinites

    Science.gov (United States)

    Cardace, D.; Meyer-Dombard, D. R.

    2011-12-01

    Serpentinization is the aqueous alteration of ultramafic (Fe- and Mg-rich) rocks, resulting in secondary mineral assemblages of serpentine, brucite, iron oxyhydroxides and magnetite, talc, and possibly carbonate and silica-rich veins and other minor phases-all depending on the evolving pressure-temperature-composition of the system. The abiotic evolution of hydrogen and possibly organic compounds via serpentinization (McCollom and Bach, 2009) highlights the relevance of this geologic process to carbon and energy sources for the deep biosphere. Serpentinization may fuel life over long stretches of geologic time, throughout the global seabed and in exposed, faulted peridotite blocks (as at Lost City Hydrothermal Field, Kelley et al., 2005), and in obducted oceanic mantle units in ophiolites (e.g., Tiago et al., 2004). Relatively little work has been published on life in continental serpentinite settings, though they likely host a unique resident microbiota. In this work, we systematically model the serpentinizing fluid as an environmental niche. Reported field data for high and moderate pH serpentinizing fluids were modeled from Cyprus, the Philippines, Oman, Northern California, New Caledonia, Yugoslavia, Portugal, Italy, Newfoundland Canada, New Zealand, and Turkey. Values for Gibbs Energy of reaction (ΔGr), kJ per mole of electrons transferred for a given metabolism, are calculated for each field site. Cases are considered both for (1) modest assumptions of 1 nanomolar hydrogen and 1 micromolar methane, based on unpublished data for a similar northern California field site (Cardace and Hoehler, in prep.) and (2) an upper estimate of 10 nanomolar hydrogen and 500 micromolar methane. We survey the feasibility of microbial metabolisms for key steps in the nitrogen cycle, oxidation of sulfur in pyrite, iron oxidation or reduction reactions, sulfate reduction coupled to hydrogen or methane oxidation, methane oxidation coupled to the reduction of oxygen, and

  5. Genetic evidence for the Mongolian ancestry of Kalmyks.

    Science.gov (United States)

    Nasidze, Ivan; Quinque, Dominique; Dupanloup, Isabelle; Cordaux, Richard; Kokshunova, Lyudmila; Stoneking, Mark

    2005-12-01

    The Kalmyks are an ethnic group along the lower Volga River in Russia who are thought to have migrated there from Mongolia about 300 years ago. To investigate their origins, we studied mtDNA and Y-chromosome variation in 99 Kalmyks. Both mtDNA HV1 sequences and Y-chromosome SNP haplogroups indicate a close relationship of Kalmyks with Mongolians. In addition, genetic diversity for both mtDNA and the Y chromosome are comparable in Kalmyks, Mongolians, and other Central Asian groups, indicating that the Kalmyk migration was not associated with a substantial bottleneck. The so-called "Genghis Khan" Y-chromosome short tandem repeat (STR) haplotype was found in high frequency (31.3%) among Kalmyks, further supporting a strong genetic connection between Kalmyks and Mongolians. Genetic analyses of even recent, relatively well-documented migrations such as of the Kalmyks can therefore lead to new insights concerning such migrations. PMID:16028228

  6. Zygomycetes, Microsporidia, and the Evolutionary Ancestry of Sex Determination

    OpenAIRE

    Koestler, Tina; Ebersberger, Ingo

    2011-01-01

    Zygomycetes and their alleged sister taxon, the microsporidia, exclusively share the presence of a cluster of three genes encoding a sugar transporter, a high mobility group (HMG)-type transcription factor, and an RNA helicase. In zygomycetes, the HMG-type transcription factor acts as the sole sex determinant. This intimately ties the evolutionary history of this gene cluster to the evolution of sex determination. Here, we have unraveled the relationships of the two gene clusters by vicarious...

  7. Exploring the Y Chromosomal Ancestry of Modern Panamanians

    OpenAIRE

    Grugni, Viola; Battaglia, Vincenza; Perego, Ugo Alessandro; Raveane, Alessandro; Lancioni, Hovirag; OLIVIERI, ANNA; Ferretti, Luca; Woodward, Scott R.; Pascale, Juan Miguel; Cooke, Richard; Myres, Natalie; Motta, Jorge; Torroni, Antonio; Achilli, Alessandro; Semino, Ornella

    2015-01-01

    Geologically, Panama belongs to the Central American land-bridge between North and South America crossed by Homo sapiens >14 ka ago. Archaeologically, it belongs to a wider Isthmo-Colombian Area. Today, seven indigenous ethnic groups account for 12.3% of Panama’s population. Five speak Chibchan languages and are characterized by low genetic diversity and a high level of differentiation. In addition, no evidence of differential structuring between maternally and paternally inherited genes has ...

  8. Enhanced statistical tests for GWAS in admixed populations: assessment using African Americans from CARe and a Breast Cancer Consortium.

    Directory of Open Access Journals (Sweden)

    Bogdan Pasaniuc

    2011-04-01

    Full Text Available While genome-wide association studies (GWAS have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously considered SNP association (LD mapping or admixture association (mapping by admixture-LD, but not both. Here, we introduce a new statistical framework for combining SNP and admixture association in case-control studies, as well as methods for local ancestry-aware imputation. We illustrate the gain in statistical power achieved by these methods by analyzing data of 6,209 unrelated African Americans from the CARe project genotyped on the Affymetrix 6.0 chip, in conjunction with both simulated and real phenotypes, as well as by analyzing the FGFR2 locus using breast cancer GWAS data from 5,761 African-American women. We show that, at typed SNPs, our method yields an 8% increase in statistical power for finding disease risk loci compared to the power achieved by standard methods in case-control studies. At imputed SNPs, we observe an 11% increase in statistical power for mapping disease loci when our local ancestry-aware imputation framework and the new scoring statistic are jointly employed. Finally, we show that our method increases statistical power in regions harboring the causal SNP in the case when the causal SNP is untyped and cannot be imputed. Our methods and our publicly available software are broadly applicable to GWAS in admixed populations.

  9. Admixture mapping of 15,280 African Americans identifies obesity susceptibility loci on chromosomes 5 and X.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    2009-05-01

    Full Text Available The prevalence of obesity (body mass index (BMI > or =30 kg/m(2 is higher in African Americans than in European Americans, even after adjustment for socioeconomic factors, suggesting that genetic factors may explain some of the difference. To identify genetic loci influencing BMI, we carried out a pooled analysis of genome-wide admixture mapping scans in 15,280 African Americans from 14 epidemiologic studies. Samples were genotyped at a median of 1,411 ancestry-informative markers. After adjusting for age, sex, and study, BMI was analyzed both as a dichotomized (top 20% versus bottom 20% and a continuous trait. We found that a higher percentage of European ancestry was significantly correlated with lower BMI (rho = -0.042, P = 1.6x10(-7. In the dichotomized analysis, we detected two loci on chromosome X as associated with increased African ancestry: the first at Xq25 (locus-specific LOD = 5.94; genome-wide score = 3.22; case-control Z = -3.94; and the second at Xq13.1 (locus-specific LOD = 2.22; case-control Z = -4.62. Quantitative analysis identified a third locus at 5q13.3 where higher BMI was highly significantly associated with greater European ancestry (locus-specific LOD = 6.27; genome-wide score = 3.46. Further mapping studies with dense sets of markers will be necessary to identify the alleles in these regions of chromosomes X and 5 that may be associated with variation in BMI.

  10. Identification, Replication, and Fine-Mapping of Loci Associated with Adult Height in Individuals of African Ancestry

    NARCIS (Netherlands)

    N'Diaye, Amidou; Chen, Gary K.; Palmer, Cameron D.; Ge, Bing; Tayo, Bamidele; Mathias, Rasika A.; Ding, Jingzhong; Nalls, Michael A.; Adeyemo, Adebowale; Adoue, Veronique; Ambrosone, Christine B.; Atwood, Larry; Bandera, Elisa V.; Becker, Lewis C.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Boerwinkle, Eric; Britton, Angela; Casey, Graham; Chanock, Stephen J.; Demerath, Ellen; Deming, Sandra L.; Diver, W. Ryan; Fox, Caroline; Harris, Tamara B.; Hernandez, Dena G.; Hu, Jennifer J.; Ingles, Sue A.; John, Esther M.; Johnson, Craig; Keating, Brendan; Kittles, Rick A.; Kolonel, Laurence N.; Kritchevsky, Stephen B.; Le Marchand, Loic; Lohman, Kurt; Liu, Jiankang; Millikan, Robert C.; Murphy, Adam; Musani, Solomon; Neslund-Dudas, Christine; North, Kari E.; Nyante, Sarah; Ogunniyi, Adesola; Ostrander, Elaine A.; Papanicolaou, George; Patel, Sanjay; Pettaway, Curtis A.; Press, Michael F.; Redline, Susan; Rodriguez-Gil, Jorge L.; Rotimi, Charles; Rybicki, Benjamin A.; Salako, Babatunde; Schreiner, Pamela J.; Signorello, Lisa B.; Singleton, Andrew B.; Stanford, Janet L.; Stram, Alex H.; Stram, Daniel O.; Strom, Sara S.; Suktitipat, Bhoom; Thun, Michael J.; Witte, John S.; Yanek, Lisa R.; Ziegler, Regina G.; Zheng, Wei; Zhu, Xiaofeng; Zmuda, Joseph M.; Zonderman, Alan B.; Evans, Michele K.; Liu, Yongmei; Becker, Diane M.; Cooper, Richard S.; Pastinen, Tomi; Henderson, Brian E.; Hirschhorn, Joel N.; Lettre, Guillaume; Haiman, Christopher A.

    2011-01-01

    Adult height is a classic polygenic trait of high heritability (h(2) similar to 0.8). More than 180 single nucleotide polymorphisms (SNPs), identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain similar to 10% of the varianc

  11. [Suggested mitochondrial ancestry of non-mitochondrial ATP/ADP].

    Science.gov (United States)

    Emel'ianov, V V

    2007-01-01

    One of the major evolutionary events that transformed endosymbiotic bacterium into mitochondrion was an acquisition of ATP/ADP carrier in order to supply the host with respiration-derived ATP. Along with mitochondrial carrier, unrelated carrier is known which is characteristic of intracellular chlamydiae, plastids, parasitic intracellular eukaryote Encephalitozoon cuniculi, and the genus Rickettsia of obligate endosymbiotic alpha-Proteobacteria. This non-mitochondrial ATP/ADP carrier was recently described in rickettsia-like endosymbionts - a group of obligate intracellular bacteria, classified with the order Rickettsiales, which have diverged after free-living alpha-Proteobacteria but before sister groups of the Rickettsiaceae assemblage (true rickettsiae) and mitochondria. Published controversial phylogenetic data on the non-mitochondrial carrier were reanalysed in the present work using both DNA and protein sequences, and various methods including Bayesian analysis. The data presented are consistent with classic endosymbiont theory for the origin of mitochondria and also suggest that even last but one common ancestor of rickettsiae and organelles may have been an endosymbiotic bacterium in which ATP/ADP carrier has first originated. PMID:17380892

  12. 75 FR 24966 - Notice on Outer Continental Shelf Oil and Gas Lease Sales

    Science.gov (United States)

    2010-05-06

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Minerals Management Service Notice on Outer Continental Shelf Oil and Gas Lease Sales AGENCY: Minerals... in any other of the following groups at Outer Continental Shelf oil and gas lease sales to be...

  13. 77 FR 64826 - Notice on Outer Continental Shelf Oil and Gas Lease Sales

    Science.gov (United States)

    2012-10-23

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management (BOEM) Notice on Outer Continental Shelf Oil and Gas Lease Sales AGENCY... with any entity in any of the other following groups at Outer Continental Shelf oil and gas lease...

  14. Heart Disease and African Americans

    Science.gov (United States)

    ... Minority Population Profiles > Black/African American > Heart Disease Heart Disease and African Americans Although African American adults are ... were 30 percent more likely to die from heart disease than non-Hispanic whites. African American women are ...

  15. Infant Mortality and African Americans

    Science.gov (United States)

    ... African American > Infant Heath & Mortality Infant Mortality and African Americans African Americans have 2.2 times the infant mortality rate ... birthweight as compared to non-Hispanic white infants. African Americans had almost twice the sudden infant death syndrome ...

  16. African N Assessment

    Science.gov (United States)

    Bekunda, M.; Galford, G. L.; Hickman, J. E.; Palm, C.

    2011-12-01

    Africa's smallholder agricultural systems face unique challenges in planning for reducing poverty, concurrent with adaptation and mitigation to climate change. At continental level, policy seeks to promote a uniquely African Green Revolution to increase crop yields and food production, and improve local livelihoods. However, the consequences on the environment and climate are not clear; these pro-economic development measures should be linked to climate change adaptation and mitigation measures, and research is required to help achieve these policy proposals by identifying options, and testing impacts. In particular, increased nitrogen (N) inputs are essential for increasing food production in Africa, but are accompanied by inevitable increases in losses to the environment. These losses appear to be low at input levels promoted in agricultural development programs, while the increased N inputs both increase current food production and appear to reduce the vulnerability of food production to changes in climate. We present field and remote sensing evidence from Malawi that subsidizing improved seed and fertilizers increases resilience to drought without adding excess N to the environment. In Kenya, field research identified thresholds in N2O losses, where emissions are very low at fertilization rates of less than 200 kg ha-1. Village-scale models have identified potential inefficiencies in the food production process where the largest losses of reactive N occur, and which could be targeted to reduce the amount of N released to the environment. We further review some on-going research activities and progress in Africa that compare different methods of managing resources that target resilience in food production and adaptation to climate change, using nutrient N as an indicator, while evaluating the effects of these resource management practices on ecosystems and the environment.

  17. Seismicity of the Earth 1900-2013 East African Rift

    Science.gov (United States)

    Hayes, Gavin P.; Jones, Eric S.; Stadler, Timothy J.; Barnhart, William D.; McNamara, Daniel E.; Benz, Harley M.; Furlong, Kevin P.; Villaseñor, Antonio

    2014-01-01

    The East African Rift system (EARS) is a 3,000-km-long Cenozoic age continental rift extending from the Afar triple junction, between the horn of Africa and the Middle East, to western Mozambique. Sectors of active extension occur from the Indian Ocean, west to Botswana and the Democratic Republic of the Congo (DRC). It is the only rift system in the world that is active on a continent-wide scale, providing geologists with a view of how continental rifts develop over time into oceanic spreading centers like the Mid-Atlantic Ridge.

  18. Consumer ethnocentrism and conspicuousness of South African imports in Mozambique

    OpenAIRE

    John, Anna

    2011-01-01

    Focus of the study The study examines the nature and effects of consumer ethnocentrism and conspicuousness of imports on consumer reactions toward South African products in Mozambique. Purpose The purpose of the study is threefold: (1) to indicate those groups of Mozambican consumers who are more ethnocentric and who see greater conspicuousness in South African imports; (2) to indicate those groups of consumers whose consumer ethnocentric responses to South African versus Moza...

  19. NERO’S ANCESTRY AND THE CONSTRUCTION OF IMPERIAL IDEOLOGY IN THE EARLY EMPIRE. A METHODOLOGICAL CASE STUDY

    Directory of Open Access Journals (Sweden)

    Olivier Hekster

    2015-01-01

    Full Text Available Within the discipline of ancient history, diverse types of sources, such as coins, inscriptions, portraits and texts, are often combined to create a coherent image of a particular ruler. A good example of how such a process works is the way in which reconstructions by modern scholars of the emperor Nero tend to look for a clearly defined ‘Neronian image’, by bringing together various types of primary evidence without paying sufficient attention to these sources’ medial contexts. This article argues that such a reconstruction does not do justice to the complex and multi-layered image of the last Julio-Claudian. By focusing on one particular aspect of Neronian imagery, the propagation of this emperor’s ancestry, we will argue that different types of sources, stemming from varying contexts and addressing different groups, cannot unproblematically be combined. Through an investigation of the ancestral messages spread by imperial and provincial coins, epigraphic evidence and portraiture, it becomes clear that systematic analysis of ancient media, their various contexts and inconsistencies is needed before combining them. Such an analysis reveals patterns within the different sources and shows that, in creating imperial images, rulers were constrained by both medial and local traditions. Modern studies of ancient images should therefore consider this medial and geographical variety in order to do justice to the multi-faceted phenomenon of imperial representation.

  20. The continental free trade area

    DEFF Research Database (Denmark)

    Sandrey, Ron; Jensen, Hans Grinsted

    The Trade Law Centre (tralac) has recently capitalised upon the prerelease Version 9.2 of the Global Trade Analysis Project (GTAP) database and the recent excellent data sets from the World Bank and other publishing quality data on trade barriers across the African continent. It undertook a series...... of simulations examining regional integration and intra-African trade barrier reductions. The results for tariff elimination on intra-African trade are promising. But the real news is in confirming that these barriers are not as significant as the various trade-related barriers except for tariffs. Especially...... outcome from all three are likely to be cumulative and generate very large gains to Africa. The overall results from especially time-in-transit costs support the current emphasis on projects such as the World Trade Organisation (WTO) infrastructural supports to Africa. In addition, the World Bank...

  1. Genotype and ancestry modulate brain's DAT availability in healthy humans

    International Nuclear Information System (INIS)

    The dopamine transporter (DAT) is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3) is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET) with [11C] cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms - 3-UTR- and intron 8- VNTRs. The main findings are the following: (1) both polymorphisms analyzed as single genetic markers and in combination (haplotype) modulate DAT density in midbrain; (2) ethnic background and age influence the strength of these associations; and (3) age-related changes in DAT availability differ in the 3-UTR and intron8 - genotype groups.

  2. Genotype and ancestry modulate brain's DAT availability in healthy humans.

    Directory of Open Access Journals (Sweden)

    Elena Shumay

    Full Text Available The dopamine transporter (DAT is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3 is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET with [¹¹C]cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms--3-UTR- and intron 8--VNTRs. The main findings are the following: 1 both polymorphisms analyzed as single genetic markers and in combination (haplotype modulate DAT density in midbrain; 2 ethnic background and age influence the strength of these associations; and 3 age-related changes in DAT availability differ in the 3-UTR and intron 8--genotype groups.

  3. Local Ancestry Inference in a Large US-Based Hispanic/Latino Study: Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

    OpenAIRE

    Browning, Sharon R.; Kelsey Grinde; Anna Plantinga; Gogarten, Stephanie M.; Stilp, Adrienne M.; Kaplan, Robert C.; M. Larissa Avilés-Santa; Browning, Brian L; Laurie, Cathy C.

    2016-01-01

    We estimated local ancestry on the autosomes and X chromosome in a large US-based study of 12,793 Hispanic/Latino individuals using the RFMix method, and we compared different reference panels and approaches to local ancestry estimation on the X chromosome by means of Mendelian inconsistency rates as a proxy for accuracy. We developed a novel and straightforward approach to performing ancestry-specific PCA after finding artifactual behavior in the results from an existing approach. Using the ...

  4. Polymorphisms in the non-muscle myosin heavy chain gene (MYH9 are associated with lower glomerular filtration rate in mixed ancestry diabetic subjects from South Africa.

    Directory of Open Access Journals (Sweden)

    Tandi Edith Matsha

    Full Text Available OBJECTIVE: Though single nucleotide polymorphisms (SNPs in the non-muscle myosin gene (MYH9 have been reported to explain most of the excess risk of nondiabetic chronic kidney disease (CKD, in African-Americans, some studies have also shown associations with diabetic end-stage renal disease. We investigated the association of MYH9 SNPs with renal traits in a mixed-ancestry South African population prone to diabetes. RESEARCH DESIGN AND METHODS: Three SNPs known to be associated with CKD (rs4821480, rs5756152 and rs12107 were genotyped using Taqman assay in 716 adults (198 with diabetes from the Bellville-South community, Cape Town. Glomerular filtration rate was estimated (eGFR and urinary albumin/creatinine ratio (ACR assessed. Multivariable regressions were used to relate the SNPs with renal traits. RESULTS: Mean age was 53.6 years, with the expected differences observed in characteristics by diabetic status. Significant associations were found between rs575152 and serum creatinine, and eGFR in the total population, and in diabetic participants (all p≤0.003, but not in non-diabetics (all p≥0.16, with significant interactions by diabetes status (interaction-p≤0.009. The association with ACR was borderline in diabetic participants (p = 0.05 and non-significant in non-diabetics (p = 0.85, with significant interaction (interaction p = 0.02. rs12107 was associated with fasting-, 2-hour glucose and HbA1c in diabetic participants only (interaction-p≤0.003, but not with renal traits. CONCLUSION: MYH9 SNPs were associated with renal traits only in diabetic participants in this population. Our findings and other studies suggest that MYH9 may have a broader genetic risk effect on kidney diseases.

  5. Post-collisional Pan-African granitoids and rare metal pegmatites in western Nigeria: Age, petrogenesis, and the 'pegmatite conundrum'

    Science.gov (United States)

    Goodenough, K. M.; Lusty, P. A. J.; Roberts, N. M. W.; Key, R. M.; Garba, A.

    2014-07-01

    The Minna area of western Nigeria lies within a Pan-African orogenic belt that extends along the margin of the West African Craton, from Algeria southwards through Nigeria, Benin and Ghana, and into the Borborema Province of Brazil. This belt is characterised by voluminous post-collisional granitoid plutons that are well exposed around the city of Minna. In this paper we present new information about their age and petrogenesis. The Pan-African plutons around Minna can be divided into two main groups: a group of largely peraluminous biotite-muscovite granites that show varying levels of deformation in late Pan-African shear zones; and a younger group of relatively undeformed, predominantly metaluminous hornblende granitoids. Pegmatites, including both barren and rare-metal types, occur at the margins of some of the plutons. New U-Pb zircon dating presented here, in combination with published data, indicates an early phase of magmatism at c. 790-760 Ma in the Minna area. This magmatism could be related either to continental rifting, or to subduction around the margins of an existing continent. The peraluminous biotite-muscovite granites were intruded at c. 650-600 Ma during regional shearing in the orogenic belt, and are likely to have formed largely by crustal melting. Subsequent emplacement of metaluminous granitoids at c. 590 Ma indicates the onset of post-orogenic extension in this area, with a contribution from mantle-derived magmas. The rare-metal pegmatites represent the youngest intrusions in this area and thus are likely to have formed in a separate magmatic episode, post-dating granite intrusion.

  6. African Americans and Glaucoma

    Science.gov (United States)

    ... Involved News About Us Donate In This Section African Americans and Glaucoma email Send this article to ... glaucoma is the leading cause of blindness in African Americans. Half of those with glaucoma don't ...

  7. Diabetes in African Americans

    OpenAIRE

    Marshall, M.

    2005-01-01

    African Americans have a high risk for type 2 diabetes. Genetic traits, the prevalence of obesity, and insulin resistance all contribute to the risk of diabetes in the African American community. African Americans have a high rate of diabetic complications, because of poor glycaemic control and racial disparities in health care in the USA. African Americans with diabetes may have an atypical presentation that simulates type 1 diabetes, but then their subsequent clinical course is typical of t...

  8. Comparative Study of Statistical Skin Detection Algorithms for Sub-Continental Human Images

    CERN Document Server

    Tabassum, Mirza Rehenuma; Kamal, Md Mostafa; Muctadir, Hossain Muhammad; Ibrahim, Muhammad; Shakir, Asif Khan; Imran, Asif; Islamm, Saiful; Rabbani, Md Golam; Khaled, Shah Mostafa; Islam, Md Saiful; Begum, Zerina; 10.3923/itj.2010.811.817

    2010-01-01

    Object detection has been a focus of research in human-computer interaction. Skin area detection has been a key to different recognitions like face recognition, human motion detection, pornographic and nude image prediction, etc. Most of the research done in the fields of skin detection has been trained and tested on human images of African, Mongolian and Anglo-Saxon ethnic origins. Although there are several intensity invariant approaches to skin detection, the skin color of Indian sub-continentals have not been focused separately. The approach of this research is to make a comparative study between three image segmentation approaches using Indian sub-continental human images, to optimize the detection criteria, and to find some efficient parameters to detect the skin area from these images. The experiments observed that HSV color model based approach to Indian sub-continental skin detection is more suitable with considerable success rate of 91.1% true positives and 88.1% true negatives.

  9. MISCONCEPTIONS OF DEPRESSION IN AFRICAN AMERICANS

    Directory of Open Access Journals (Sweden)

    Zohaib eSohail

    2014-06-01

    Full Text Available Major depression is a very common disabling disorder. Although the relationship between race and depression is complex, depression affects all races, all ethnic and geographic locations as well as all age groups. The prevalence of depression in African Americans is controversial, due to the paucity of research. The deficit in the knowledge and skills in treating depression in African Americans have not been adequately addressed so far. Inadequate and insufficient data on African Americans contributes to the problems of under diagnoses, misdiagnosis and under treatment of depression. This article will highlight the existing problem of depression in Afro American with a focus on diagnostic and treatment issues.

  10. Sediment-hosted stratabound copper assessment of the Neoproterozoic Roan Group, central African copperbelt, Katanga Basin, Democratic Republic of the Congo and Zambia: Chapter T in Global mineral resource assessment

    Science.gov (United States)

    Zientek, Michael L.; Bliss, James D.; Broughton, David W.; Christie, Michael; Denning, Paul D.; Hayes, Timothy S.; Hitzman, Murray W.; Horton, John D.; Frost-Killian, Susan; Jack, Douglas J.; Master, Sharad; Parks, Heather L.; Taylor, Cliff D.; Wilson, Anna B.; Wintzer, Niki E.; Woodhead, Jon

    2014-01-01

    This study estimates the location, quality, and quantity of undiscovered copper in stratabound deposits within the Neoproterozoic Roan Group of the Katanga Basin in the Democratic Republic of the Congo and Zambia. The study area encompasses the Central African Copperbelt, the greatest sediment-hosted copper-cobalt province in the world, containing 152 million metric tons of copper in greater than 80 deposits. This study (1) delineates permissive areas (tracts) where undiscovered sediment-hosted stratabound copper deposits may occur within 2 kilometers of the surface, (2) provides a database of known sediment-hosted stratabound copper deposits and prospects, (3) estimates numbers of undiscovered deposits within these permissive tracts at several levels of confidence, and (4) provides probabilistic estimates of amounts of copper and mineralized rock that could be contained in undiscovered deposits within each tract. The assessment, conducted in January 2010 using a three-part form of mineral resource assessment, indicates that a substantial amount of undiscovered copper resources might occur in sediment-hosted stratabound copper deposits within the Roan Group in the Katanga Basin. Monte Carlo simulation results that combine grade and tonnage models with estimates of undiscovered deposits indicate that the mean estimate of undiscovered copper in the study area is 168 million metric tons, which is slightly greater than the known resources at 152 million metric tons. Furthermore, significant value can be expected from associated metals, particularly cobalt. Tracts in the Democratic Republic of the Congo (DRC) have potential to contain near-surface, undiscovered deposits. Monte Carlo simulation results indicate a mean value of 37 million metric tons of undiscovered copper may be present in significant prospects.

  11. African American Suicide

    Science.gov (United States)

    African American Suicide Fact Sheet Based on 2012 Data (2014) Overview • In 2012, 2,357 African Americans completed suicide in the U.S. Of these, ... 46 per 100,000. • The suicide rate for African Americans ages 10-19 was 2.98 per ...

  12. Nigeria's infrastructure : a continental perspective

    OpenAIRE

    Foster, Vivien; Pushak, Nataliya

    2011-01-01

    Infrastructure made a net contribution of around one percentage point to Nigeria's improved per capita growth performance in recent years, in spite of the fact that unreliable power supplies held growth back. Raising the country's infrastructure endowment to that of the region's middle-income countries could boost annual growth by around 4 percentage points. Among its African peers, Nigeri...

  13. The contribution of ancestry, chance, and past and ongoing selection to adaptive evolution

    Indian Academy of Sciences (India)

    Amitabh Joshi; Robinson B. Castillo; Laurence D. Mueller

    2003-12-01

    The relative contributions of ancestry, chance, and past and ongoing selection to variation in one adaptive (larval feeding rate) and one seemingly nonadaptive (pupation height) trait were determined in populations of Drosophila melanogaster adapting to either low or high larval densities in the laboratory. Larval feeding rates increased rapidly in response to high density, and the effects of ancestry, past selection and chance were ameliorated by ongoing selection within 15–20 generations. Similarly, in populations previously kept at high larval density, and then switched to low larval density, the decline of larval feeding rate to ancestral levels was rapid (15–20 generations) and complete, providing support for a previously stated hypothesis regarding the costs of faster feeding in Drosophila larvae. Variation among individuals was the major contributor to variation in pupation height, a trait that would superficially appear to be nonadaptive in the environmental context of the populations used in this study because it did not diverge between sets of populations kept at low versus high larval density for many generations. However, the degree of divergence among populations ($F_{\\text{ST}}$) for pupation height was significantly less than expected for a selectively neutral trait, and we integrate results from previous studies to suggest that the variation for pupation height among populations is constrained by stabilizing selection, with a flat, plateau-like fitness function that, consequently, allows for substantial phenotypic variation within populations. Our results support the view that the genetic imprints of history (ancestry and past selection) in outbreeding sexual populations are typically likely to be transient in the face of ongoing selection and recombination. The results also illustrate the heuristic point that different forms of selection—for example directional versus stabilizing selection—acting on a trait in different populations may

  14. Meta-analysis of genome-wide association studies in African Americans provides insights into the genetic architecture of type 2 diabetes.

    Science.gov (United States)

    Ng, Maggie C Y; Shriner, Daniel; Chen, Brian H; Li, Jiang; Chen, Wei-Min; Guo, Xiuqing; Liu, Jiankang; Bielinski, Suzette J; Yanek, Lisa R; Nalls, Michael A; Comeau, Mary E; Rasmussen-Torvik, Laura J; Jensen, Richard A; Evans, Daniel S; Sun, Yan V; An, Ping; Patel, Sanjay R; Lu, Yingchang; Long, Jirong; Armstrong, Loren L; Wagenknecht, Lynne; Yang, Lingyao; Snively, Beverly M; Palmer, Nicholette D; Mudgal, Poorva; Langefeld, Carl D; Keene, Keith L; Freedman, Barry I; Mychaleckyj, Josyf C; Nayak, Uma; Raffel, Leslie J; Goodarzi, Mark O; Chen, Y-D Ida; Taylor, Herman A; Correa, Adolfo; Sims, Mario; Couper, David; Pankow, James S; Boerwinkle, Eric; Adeyemo, Adebowale; Doumatey, Ayo; Chen, Guanjie; Mathias, Rasika A; Vaidya, Dhananjay; Singleton, Andrew B; Zonderman, Alan B; Igo, Robert P; Sedor, John R; Kabagambe, Edmond K; Siscovick, David S; McKnight, Barbara; Rice, Kenneth; Liu, Yongmei; Hsueh, Wen-Chi; Zhao, Wei; Bielak, Lawrence F; Kraja, Aldi; Province, Michael A; Bottinger, Erwin P; Gottesman, Omri; Cai, Qiuyin; Zheng, Wei; Blot, William J; Lowe, William L; Pacheco, Jennifer A; Crawford, Dana C; Grundberg, Elin; Rich, Stephen S; Hayes, M Geoffrey; Shu, Xiao-Ou; Loos, Ruth J F; Borecki, Ingrid B; Peyser, Patricia A; Cummings, Steven R; Psaty, Bruce M; Fornage, Myriam; Iyengar, Sudha K; Evans, Michele K; Becker, Diane M; Kao, W H Linda; Wilson, James G; Rotter, Jerome I; Sale, Michèle M; Liu, Simin; Rotimi, Charles N; Bowden, Donald W

    2014-08-01

    Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15 × 10(-94)liability scale in African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies. PMID:25102180

  15. African American Culture and Hypertension Prevention

    OpenAIRE

    Peters, Rosalind M.; Aroian, Karen J.; Flack, John M.

    2006-01-01

    A qualitative study was done to explore attitudes and beliefs of African Americans regarding hypertension-preventive self-care behaviors. Five focus groups, with 34 participants, were held using interview questions loosely based on the Theory of Planned Behavior (TPB). Analysis revealed themes broadly consistent with the TPB, and also identified an overarching theme labeled “circle of culture.” The circle is a metaphor for ties that bind individuals within the larger African American communit...

  16. Discussion of Continental Rifts and Their Structure

    Science.gov (United States)

    Gilbert, M. C.

    2011-12-01

    When continental crust rifts, two chief modifications of that crust occur: 1)stretching of older, existing crust; 2)addition of new rift mass--sediments and mantle mafic units. However, paleorifts, such as the Cambrian Southern Oklahoma Aulacogen differ from neorifts, such as the East African. Much of this difference may be reflected in the nature of the lower rift crust. Stretching of the upper crust is accomplished primarily through faulting while the lower crust flows. Concurrently addition of sediments occurs in downdropped faulted blocks in the upper crust, and of mafic magmas risen and emplaced as intrusive layered complexes through the rift and as extrusive flows. All this happens in a regime of higher temperatures and higher heat flow. Consequences of this can include either melting of the stretched existing crust, or direct fractionation of rising mafic magma or melting of already crystallized mafic complexes, forming new silicic magmas. Geochemistry of these different magmatic bodies elucidates which of these possible processes seems dominant. Most geophysical studies of rifts have two results: 1)higher gravity anomalies indicating addition of new mafic masses, usually interpreted to be concentrated in the upper rift crust; and 2)seismic characteristics indicating crustal mottling and layering of the upper rift crust. What is not clearly indicated is nature of the lower crust, and of the mantle-crust contact (M discontinuity). Comparison of paleorifts and neorifts, and later geological history of paleorifts, suggests interesting interpretations of lower rift crust,especially in paleorifts, and some of the difficulties in sorting out answers.

  17. Facts about Peripheral Arterial Disease (P.A.D.) for African Americans

    Science.gov (United States)

    ... About Peripheral Arterial Disease (P.A.D.) for African Americans One in every 20 Americans over the age ... stroke. P.A.D. is more common in African Americans than any other racial or ethnic group. This ...

  18. Continental crust beneath southeast Iceland.

    Science.gov (United States)

    Torsvik, Trond H; Amundsen, Hans E F; Trønnes, Reidar G; Doubrovine, Pavel V; Gaina, Carmen; Kusznir, Nick J; Steinberger, Bernhard; Corfu, Fernando; Ashwal, Lewis D; Griffin, William L; Werner, Stephanie C; Jamtveit, Bjørn

    2015-04-14

    The magmatic activity (0-16 Ma) in Iceland is linked to a deep mantle plume that has been active for the past 62 My. Icelandic and northeast Atlantic basalts contain variable proportions of two enriched components, interpreted as recycled oceanic crust supplied by the plume, and subcontinental lithospheric mantle derived from the nearby continental margins. A restricted area in southeast Iceland--and especially the Öræfajökull volcano--is characterized by a unique enriched-mantle component (EM2-like) with elevated (87)Sr/(86)Sr and (207)Pb/(204)Pb. Here, we demonstrate through modeling of Sr-Nd-Pb abundances and isotope ratios that the primitive Öræfajökull melts could have assimilated 2-6% of underlying continental crust before differentiating to more evolved melts. From inversion of gravity anomaly data (crustal thickness), analysis of regional magnetic data, and plate reconstructions, we propose that continental crust beneath southeast Iceland is part of ∼350-km-long and 70-km-wide extension of the Jan Mayen Microcontinent (JMM). The extended JMM was marginal to East Greenland but detached in the Early Eocene (between 52 and 47 Mya); by the Oligocene (27 Mya), all parts of the JMM permanently became part of the Eurasian plate following a westward ridge jump in the direction of the Iceland plume. PMID:25825769

  19. Evaluation of the metabochip genotyping array in African Americans and implications for fine mapping of GWAS-identified loci: the PAGE study.

    Directory of Open Access Journals (Sweden)

    Steven Buyske

    Full Text Available The Metabochip is a custom genotyping array designed for replication and fine mapping of metabolic, cardiovascular, and anthropometric trait loci and includes low frequency variation content identified from the 1000 Genomes Project. It has 196,725 SNPs concentrated in 257 genomic regions. We evaluated the Metabochip in 5,863 African Americans; 89% of all SNPs passed rigorous quality control with a call rate of 99.9%. Two examples illustrate the value of fine mapping with the Metabochip in African-ancestry populations. At CELSR2/PSRC1/SORT1, we found the strongest associated SNP for LDL-C to be rs12740374 (p = 3.5 × 10(-11, a SNP indistinguishable from multiple SNPs in European ancestry samples due to high correlation. Its distinct signal supports functional studies elsewhere suggesting a causal role in LDL-C. At CETP we found rs17231520, with risk allele frequency 0.07 in African Americans, to be associated with HDL-C (p = 7.2 × 10(-36. This variant is very rare in Europeans and not tagged in common GWAS arrays, but was identified as associated with HDL-C in African Americans in a single-gene study. Our results, one narrowing the risk interval and the other revealing an associated variant not found in Europeans, demonstrate the advantages of high-density genotyping of common and rare variation for fine mapping of trait loci in African American samples.

  20. 76 FR 4129 - Notice on Outer Continental Shelf Oil and Gas Lease Sales

    Science.gov (United States)

    2011-01-24

    ... Gas Lease Sales AGENCY: Bureau of Ocean Energy Management, Regulation and Enforcement, Interior... any entity in any other of the following groups at Outer Continental Shelf oil and gas lease sales...

  1. 76 FR 28449 - Notice on Outer Continental Shelf Oil and Gas Lease Sales

    Science.gov (United States)

    2011-05-17

    ... Oil and Gas Lease Sales AGENCY: Bureau of Ocean Energy Management, Regulation and Enforcement... with any entity in any other of the following groups at Outer Continental Shelf oil and gas lease...

  2. Ancestry-informative markers on chromosomes 2, 8 and 15 are associated with insulin-related traits in a racially diverse sample of children

    Directory of Open Access Journals (Sweden)

    Klimentidis Yann C

    2011-01-01

    Full Text Available Abstract Type 2 diabetes represents an increasing health burden. Its prevalence is rising among younger age groups and differs among racial/ethnic groups. Little is known about its genetic basis, including whether there is a genetic basis for racial/ethnic disparities. We examined a multi-ethnic sample of 253 healthy children to evaluate associations between insulin-related phenotypes and 142 ancestry-informative markers (AIMs, while adjusting for sex, age, Tanner stage, genetic admixture, total body fat, height and socio-economic status. We also evaluated the effect of measurement errors in the estimation of the individual ancestry proportions on the regression results. We found that European genetic admixture is positively associated with insulin sensitivity (SI, and negatively associated with the acute insulin response to glucose, fasting insulin levels and the homeostasis model assessment of insulin resistance. Our analysis revealed associations between individual AIMs on chromosomes 2, 8 and 15 and these phenotypes. Most notably, marker rs3287 at chromosome 2p21 was found to be associated with SI (p = 5.8 × 10-5. This marker may be in admixture linkage disequilibrium with nearby loci (THADA and BCL11A that previously have been reported to be associated with diabetes and diabetes-related phenotypes in several genome-wide association and linkage studies. Our results provide further evidence that variation in the 2p21 region containing THADA and BCL11A is associated with type 2 diabetes. Importantly, we have implicated this region in the early development of diabetes-related phenotypes, and in the genetic aetiology of population differences in these phenotypes.

  3. Structural and lithological controls of gold-bearing veins associated with the Brasiliano-Pan African Orogeny: An example from the Buracão Area, Araí Group (Brasília Fold Belt, Brazil)

    Science.gov (United States)

    Pires, Gustavo Luiz Campos; Bongiolo, Everton Marques; Renac, Christophe; Nascimento, Débora Barros; Prado, Maurício

    2016-03-01

    The Buracão area, Central Brazil, comprises a group of structurally-controlled vein-type gold prospects, hosted in the metasedimentary Traíras Fm. of the Araí Group. This group records all tectonic stages of the Statherian taphrogenesis in Central Brazil and represents part of the Brasília Fold Belt (BFB) developed during the Neoproterozoic Brasiliano Orogeny. Three lithostratigraphic units were identified at the study area: two phyllitic and one composed of intercalation of quartzite and carbonaceous/sericite phyllites that hosted the Au mineralized vein systems. These units were metamorphosed to the biotite zone, greenschist facies. The high-grade mineralization (up to 31 g/t) occurs as subvertical zoned or massive veins with quartz, white mica, Fe-sulfides and Fe-oxides oriented in four main directions (i.e. N50°E; N°20E; N-S and E-W). Two deformational phases, each subdivided in two stages (D1a, D1b, D2a and D2b) were recognized in the study area. These deformational phases comprise different sets of structures, such as foliations, folds, faults, fractures and veins that represent regional deformational events on subordinated scale. The D1a and D1b stages represent the regional N-S trending thrust fronts and propagation folding developed during the evolution of W-E shortening, respectively. The D2a and D2b were correlated to the development and reactivation of regional-scale N- and NE-trending transpressive shear systems at different crustal levels, respectively. The gold-bearing quartz veins were developed during D2a stage as a complex shear fracture set according to a Riedel system, representing subordinated structures of the regional transpressive system. The structurally-controlled gold occurrences of the Buracão area is an example of orogenic vein-type gold mineralization developed during the Brasiliano-Pan African Orogeny at the BFB in Central Brazil. Our work suggests that this poorly studied part of BFB has good potential for additional high

  4. Ancestry of the Iban is predominantly Southeast Asian: genetic evidence from autosomal, mitochondrial, and Y chromosomes.

    Directory of Open Access Journals (Sweden)

    Tatum S Simonson

    Full Text Available Humans reached present-day Island Southeast Asia (ISEA in one of the first major human migrations out of Africa. Population movements in the millennia following this initial settlement are thought to have greatly influenced the genetic makeup of current inhabitants, yet the extent attributed to different events is not clear. Recent studies suggest that south-to-north gene flow largely influenced present-day patterns of genetic variation in Southeast Asian populations and that late Pleistocene and early Holocene migrations from Southeast Asia are responsible for a substantial proportion of ISEA ancestry. Archaeological and linguistic evidence suggests that the ancestors of present-day inhabitants came mainly from north-to-south migrations from Taiwan and throughout ISEA approximately 4,000 years ago. We report a large-scale genetic analysis of human variation in the Iban population from the Malaysian state of Sarawak in northwestern Borneo, located in the center of ISEA. Genome-wide single-nucleotide polymorphism (SNP markers analyzed here suggest that the Iban exhibit greatest genetic similarity to Indonesian and mainland Southeast Asian populations. The most common non-recombining Y (NRY and mitochondrial (mt DNA haplogroups present in the Iban are associated with populations of Southeast Asia. We conclude that migrations from Southeast Asia made a large contribution to Iban ancestry, although evidence of potential gene flow from Taiwan is also seen in uniparentally inherited marker data.

  5. Ancestry of the Iban is predominantly Southeast Asian: genetic evidence from autosomal, mitochondrial, and Y chromosomes.

    Science.gov (United States)

    Simonson, Tatum S; Xing, Jinchuan; Barrett, Robert; Jerah, Edward; Loa, Peter; Zhang, Yuhua; Watkins, W Scott; Witherspoon, David J; Huff, Chad D; Woodward, Scott; Mowry, Bryan; Jorde, Lynn B

    2011-01-01

    Humans reached present-day Island Southeast Asia (ISEA) in one of the first major human migrations out of Africa. Population movements in the millennia following this initial settlement are thought to have greatly influenced the genetic makeup of current inhabitants, yet the extent attributed to different events is not clear. Recent studies suggest that south-to-north gene flow largely influenced present-day patterns of genetic variation in Southeast Asian populations and that late Pleistocene and early Holocene migrations from Southeast Asia are responsible for a substantial proportion of ISEA ancestry. Archaeological and linguistic evidence suggests that the ancestors of present-day inhabitants came mainly from north-to-south migrations from Taiwan and throughout ISEA approximately 4,000 years ago. We report a large-scale genetic analysis of human variation in the Iban population from the Malaysian state of Sarawak in northwestern Borneo, located in the center of ISEA. Genome-wide single-nucleotide polymorphism (SNP) markers analyzed here suggest that the Iban exhibit greatest genetic similarity to Indonesian and mainland Southeast Asian populations. The most common non-recombining Y (NRY) and mitochondrial (mt) DNA haplogroups present in the Iban are associated with populations of Southeast Asia. We conclude that migrations from Southeast Asia made a large contribution to Iban ancestry, although evidence of potential gene flow from Taiwan is also seen in uniparentally inherited marker data. PMID:21305013

  6. Orthodontic probability tables for black patients of African descent: mixed dentition analysis.

    Science.gov (United States)

    Schirmer, U R; Wiltshire, W A

    1997-11-01

    Mixed dentition space analyses form an essential part of orthodontic diagnostic procedures to determine the amount of space available for the accommodation of permanent teeth. The Moyers' probability tables for computing the sizes of unerupted canines and premolars were formulated at the University of Michigan from a sample consisting of northern European white subjects and are currently used worldwide. Because tooth sizes vary significantly between different population groups, it was the purpose of this study to construct relevant probability tables that would be more applicable to black subjects. Data were collected from a series of 100 randomly selected study models of black patients. The sample was equally subdivided by gender and all subjects had Angle Class I molar relationships with only minor malocclusions such as minor crowding, rotations, or diastemas. Two investigators independently measured the teeth on the study casts with a Vernier gauge that had sharpened calliper tips. Intraexaminer and interexaminer reliability was determined at 0.2 mm. All teeth to and including the first molars were measured. These data were then utilized in regression equations for both maxillary and mandibular arches, to enable the prediction of the mesiodistal widths of the canines and two premolars. The equations and predicted values were compared with those of the Moyers' probability tables, and significant differences (p <0.05) were found (except for the prediction of maxillary canines and premolars in females at the 85 and 95 percentile probability level). New probability tables for black subjects were formulated. It is envisaged that the proposed probability tables would be more accurate for black patients of African ancestry. PMID:9387842

  7. Highly discrepant proportions of female and male Scandinavian and British Isles ancestry within the isolated population of the Faroe Islands

    DEFF Research Database (Denmark)

    Als, Thomas D; Jorgensen, Tove H; Børglum, Anders D;

    2006-01-01

    The Faroe Islands in the North Atlantic Ocean are inhabited by a small population, whose origin is thought to date back to the Viking Age. Historical, archaeological and linguistic evidence indicates that the present population of the Faroe Islands may have a mixture of Scandinavian and British...... frequency-based admixture approach taking private haplotypes into account by the use of phylogenetic information. While previous studies have suggested an excess of Scandinavian ancestry among the male settlers of the Faroe Islands, the current study indicates an excess of British Isles ancestry among the...

  8. Trans-ancestry genome-wide association study identifies 12 genetic loci influencing blood pressure and implicates a role for DNA methylation

    DEFF Research Database (Denmark)

    Kato, Norihiro; Loh, Marie; Takeuchi, Fumihiko;

    2015-01-01

    We carried out a trans-ancestry genome-wide association and replication study of blood pressure phenotypes among up to 320,251 individuals of East Asian, European and South Asian ancestry. We find genetic variants at 12 new loci to be associated with blood pressure (P = 3.9 × 10(-11) to 5.0 × 10(...

  9. Older African American Women’s Lived Experiences with Depression

    OpenAIRE

    Ward, Earlise C.; Mengesha, Maigenete; Issa, Fathiya

    2013-01-01

    Little is known about older African American women’s lived experiences with depression. What does depression mean to this group? What are they doing about their depression? Unfortunately, these questions are unanswered. This study examined older African American women’s lived experiences with depression and coping behaviours. The common sense model provided the theoretical framework for present study. Thirteen community-dwelling African American women aged 60 and older (M =71 years) participa...

  10. Worldwide cutaneous malignant melanoma incidences analyzed by sex, age, and skin type over time (1955-2007): Is HPV infection of androgenic hair follicular melanocytes a risk factor for developing melanoma exclusively in people of European-ancestry?

    Science.gov (United States)

    Merrill, Stephen J; Subramanian, Madhan; Godar, Dianne E

    2016-01-01

    The cutaneous malignant melanoma (CMM) incidence has been increasing in an exponential manner in certain populations around the world for over 7 decades. To help illuminate the etiology, we performed worldwide temporal (1955-2007) CMM incidence analysis by sex, age (0-14, 15-29, 30-49, 50-69, 70-85+), and skin type on 6 continents using data from the International Agency for Research on Cancer. We observe an exponential increase in the CMM incidence over time and an increase of about 2 orders of magnitude between age groups 0-14 and 15-29 exclusively in European-ancestry populations around the world independent of skin type (I-III or III-IV). Other populations like the Chinese (III-IV) had much lower CMM incidences that either remained stable or temporally decreased but did not display a dramatic increase between the youngest age groups. The dramatic increase in the incidence between the youngest age groups found only in European-ancestry populations suggests one of the most important risk factors for CMM may be developing androgenic hair, the occurrence of which appears to correlate with the distribution of CMM over male and female body sites. Besides that potential new risk factor, the increasing CMM incidence with increasing age, known not to be from cumulative UV doses, may be associated with age-related changes to skin, i.e., thinning epidermis causing lower vitamin D3 levels, and hair, i.e., whitening from higher reactive oxygen species. The temporal exponential increasing CMM incidence in European-ancestry populations may be due to Human Papilloma Virus infection of follicular hair melanocytes, found in CMM biopsies. PMID:27588159

  11. Worldwide cutaneous malignant melanoma incidences analyzed by sex, age, and skin type over time (1955–2007): Is HPV infection of androgenic hair follicular melanocytes a risk factor for developing melanoma exclusively in people of European-ancestry?

    Science.gov (United States)

    Merrill, Stephen J.; Subramanian, Madhan; Godar, Dianne E.

    2016-01-01

    ABSTRACT The cutaneous malignant melanoma (CMM) incidence has been increasing in an exponential manner in certain populations around the world for over 7 decades. To help illuminate the etiology, we performed worldwide temporal (1955–2007) CMM incidence analysis by sex, age (0–14, 15–29, 30–49, 50–69, 70–85+), and skin type on 6 continents using data from the International Agency for Research on Cancer. We observe an exponential increase in the CMM incidence over time and an increase of about 2 orders of magnitude between age groups 0–14 and 15–29 exclusively in European-ancestry populations around the world independent of skin type (I–III or III–IV). Other populations like the Chinese (III-IV) had much lower CMM incidences that either remained stable or temporally decreased but did not display a dramatic increase between the youngest age groups. The dramatic increase in the incidence between the youngest age groups found only in European-ancestry populations suggests one of the most important risk factors for CMM may be developing androgenic hair, the occurrence of which appears to correlate with the distribution of CMM over male and female body sites. Besides that potential new risk factor, the increasing CMM incidence with increasing age, known not to be from cumulative UV doses, may be associated with age-related changes to skin, i.e., thinning epidermis causing lower vitamin D3 levels, and hair, i.e., whitening from higher reactive oxygen species. The temporal exponential increasing CMM incidence in European-ancestry populations may be due to Human Papilloma Virus infection of follicular hair melanocytes, found in CMM biopsies. PMID:27588159

  12. Seasonal Changes in Sleep Duration in African American and African College Students Living In Washington, D.C.

    Directory of Open Access Journals (Sweden)

    Janna Volkov

    2007-01-01

    Full Text Available Duration of nocturnal melatonin secretion, a marker of “biological night” that relates to sleep duration, is longer in winter than in summer in patients with seasonal affective disorder (SAD, but not in healthy controls. In this study of African and African American college students, we hypothesized that students who met criteria for winter SAD or subsyndromal SAD (S-SAD would report sleeping longer in winter than in summer. In addition, based on our previous observation that Africans report more “problems” with change in seasons than African Americans, we expected that the seasonal changes in sleep duration would be greater in African students than in African American students. Based on Seasonal Pattern Assessment Questionnaire (SPAQ responses, African American and African college students in Washington, D.C. (N = 575 were grouped into a winter SAD/S-SAD group or a no winter diagnosis group, and winter and summer sleep length were determined. We conducted a 2 (season × 2 (sex × 2 (ethnicity × 2 (winter diagnosis group ANCOVA on reported sleep duration, controlling for age. Contrary to our hypothesis, we found that African and African American students with winter SAD/S-SAD report sleeping longer in the summer than in the winter. No differences in seasonality of sleep were found between African and African American students. Students with winter SAD or S-SAD may need to sacrifice sleep duration in the winter, when their academic functioning/efficiency may be impaired by syndromal or subsyndromal depression, in order to meet seasonally increased academic demands.

  13. Adapting health promotion interventions for ethnic minority groups: a qualitative study.

    Science.gov (United States)

    Liu, Jing Jing; Davidson, Emma; Bhopal, Raj; White, Martin; Johnson, Mark; Netto, Gina; Sheikh, Aziz

    2016-06-01

    Adaptation of health interventions has garnered international support across academic disciplines and among various health organizations. Through semi-structured interviews, we sought to explore and understand the perspectives of 26 health researchers and promoters located in the USA, UK, Australia, New Zealand and Norway, working with ethnic minority populations, specifically African-, South Asian- and Chinese-origin populations in the areas of smoking cessation, increasing physical activity and healthy eating, to better understand how adaptation works in practice. We drew on the concepts of intersectionality, representation and context from feminist, sociology and human geography literature, respectively, to help us understand how adaptations for ethnic groups approach the variable of ethnicity. Findings include (i) the intersections of ethnicity and demographic variables such as age and gender highlight the different ways in which people interact, interpret and participate in adapted interventions; (ii) the representational elements of ethnicity such as ancestry or religion are more complexly lived than they are defined in adapted interventions and (iii) the contextual experiences surrounding ethnicity considerations shape the receptivity, durability and continuity of adapted interventions. In conclusion, leveraging the experience and expertise of health researchers and promoters in light of three social science concepts has deepened our understanding of how adaptation works in principle and in practice for ethnic minority populations. PMID:25561680

  14. Six new polymorphic microsatellite loci isolated and characterized from the African savannah elephant genome

    DEFF Research Database (Denmark)

    Nyakaana, Silvester; Okello, John Bosco A.; Muwanika, Vincent B.;

    2005-01-01

    The African savannah elephant (Loxodonta africana) is a 'keystone' species that plays a vital role in regulating the dynamics of both plant and animal communities and yet it is endangered and its numbers have been reduced to approximately 500 000 across their entire continental range. Molecular...

  15. African Otter Workshop

    OpenAIRE

    Jan Reed-Smith; Hughes Akpona; Grace Yoxon

    2016-01-01

    All concerned thought this was an excellent workshop with important progress made towards creating a viable beginning of an African Otter Network. There is a long road ahead but the 2015 African Otter Workshop is a start on developing range country partners, activists and researchers as well as collaborating on issue identification and resolution which will assist in preserving at least some refugia for Africa’s otters. A list of actions was agreed on, including the creation of an African Ott...

  16. Rethinking "relevance": South African psychology in context.

    Science.gov (United States)

    Long, Wahbie

    2013-02-01

    This article examines the phenomenon known as the "relevance debate" in South African psychology. It begins with a historical overview of the contours of the discipline in that country before describing the controversy's international dimensions, namely, the revolutionary politics of 1960s higher education and the subsequent emergence of cognate versions of the debate in American, European, and "Third World" psychology. The article then details how South Africa's "relevance" project enjoyed a special affinity with an assortment of ethnic-cultural, national, and continental myths and metaphors, all of which served the interests of the political formations of the day. It discusses how, in present-day South Africa, the intelligentsia has become an important catalyst for the so-called African Renaissance, which seeks to provide "relevant" solutions for the regeneration of African society. However, the global hegemony of what began in the 1970s as a "second academic revolution," aided by the lifting of the academic boycott of South Africa, has blunted the once critical edge of "relevance" discourse. A new mode of knowledge production now holds sway, the outcome of a dramatic reformulation of the capitalist manifesto in which the values of the "May 68" generation have been hijacked by a managerialist rationality. In light of the capitalization of the knowledge-production enterprise, it is concluded that the idiom of "relevance" has outlived its usefulness. PMID:23421936

  17. Age and isotope evidence for the evolution of continental crust

    International Nuclear Information System (INIS)

    Irreversible chemical differentiation of the mantle's essentially infinite reservoir for at least the past 3800 Ma has produced new continental, sialic crust during several relatively short (ca. 100-300 Ma) episodes which were widely separated in time and may have been of global extent. During each episode (termed 'accretion-differentiation superevent'), juvenile sial underwent profound igneous, metamorphic and geochemical differentiation, resulting in thick (ca. 25-40 km), stable, compositionally gradational, largely indestructible, continental crust exhibiting close grouping of isotopic ages of rock formation, as well as mantle-type initial Sr and Pb isotopic ratios for all major constituents. Isotopic evidence suggests that within most accretion-differentiation superevents - and especially during the earlier ones - continental growth predominated over reworking of older sialic crust. Reworking of older sialic crust can occur in several types of geological environment and appears to have become more prevalent with the passage of geological time. It is usually clearly distinguishable from continental growth, by application of appropriate age and isotope data. (author)

  18. Towards a holistic review of Pan-Africanism: linking the idea and the movement.

    Science.gov (United States)

    Young, Kurt B

    2010-01-01

    This article explores two general approaches to defining Pan-Africanism. Traditional Pan-Africanism reflects definitions of Pan-Africanism that begin with the assumption that distinctions must be made between early "ideas" of group identification with Africa versus modern organizational activities. However, holistic approaches emphasize the interconnectivity of Pan-African ideas and concrete activities. This discussion explores these approaches and their implications for contemporary analyses of Pan-Africanism. The essay concludes that the holistic line is best suited for developing a new model in Pan-Africanism. PMID:20648996

  19. Optimal waist-to-height ratio values for cardiometabolic risk screening in an ethnically diverse sample of South African urban and rural school boys and girls.

    Directory of Open Access Journals (Sweden)

    Tandi E Matsha

    Full Text Available BACKGROUND: The proposed waist-to-height ratio (WHtR cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value. METHODS: Metabolic syndrome (MetS components were measured in 1272 randomly selected learners, aged 10-16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden's index and the closest-top-left (CTL point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference. RESULTS: The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5, but two different values in boys, 0.455 (42.9, 88.4 and 0.425 (60.3, 67.7 based on the Youden's index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden's index0.505 (31.6, 87.1 and CTL point 0.475 (44.4, 75.9. CONCLUSION: The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.

  20. Genome-wide trans-ancestry meta-analysis provides insight into the genetic architecture of type 2 diabetes susceptibility

    DEFF Research Database (Denmark)

    Mahajan, Anubha; Go, Min Jin; Zhang, Weihua;

    2014-01-01

    To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We obs...

  1. Educational Needs and Barriers for African Refugee Students in Manitoba

    Science.gov (United States)

    Kanu, Yatta

    2008-01-01

    This study investigated the educational needs and barriers for diverse African refugee students in two inner-city high schools in Manitoba. Forty African refugee students, two principals, eight teachers, four parents, and four community leaders participated in the study. Five focus groups, individual interviews, and school and classroom…

  2. Ancestry inference in complex admixtures via variable-length Markov chain linkage models.

    Science.gov (United States)

    Rodriguez, Jesse M; Bercovici, Sivan; Elmore, Megan; Batzoglou, Serafim

    2013-03-01

    Inferring the ancestral origin of chromosomal segments in admixed individuals is key for genetic applications, ranging from analyzing population demographics and history, to mapping disease genes. Previous methods addressed ancestry inference by using either weak models of linkage disequilibrium, or large models that make explicit use of ancestral haplotypes. In this paper we introduce ALLOY, an efficient method that incorporates generalized, but highly expressive, linkage disequilibrium models. ALLOY applies a factorial hidden Markov model to capture the parallel process producing the maternal and paternal admixed haplotypes, and models the background linkage disequilibrium in the ancestral populations via an inhomogeneous variable-length Markov chain. We test ALLOY in a broad range of scenarios ranging from recent to ancient admixtures with up to four ancestral populations. We show that ALLOY outperforms the previous state of the art, and is robust to uncertainties in model parameters. PMID:23421795

  3. The dynamics of mergers and acquisitions: ancestry as the seminal determinant.

    Science.gov (United States)

    Viegas, Eduardo; Cockburn, Stuart P; Jensen, Henrik J; West, Geoffrey B

    2014-11-01

    Understanding the fundamental mechanisms behind the complex landscape of corporate mergers and acquisitions is of crucial importance to economies across the world. Adapting ideas from the fields of complexity and evolutionary dynamics to analyse business ecosystems, we show here that ancestry, i.e. the cumulative sum of historical mergers across all ancestors, is the key characteristic to company mergers and acquisitions. We verify this by comparing an agent-based model to an extensive range of business data, covering the period from the 1830s to the present day and a range of industries and geographies. This seemingly universal mechanism leads to imbalanced business ecosystems, with the emergence of a few very large, but sluggish 'too big to fail' entities, and very small, niche entities, thereby creating a paradigm where a configuration akin to effective oligopoly or monopoly is a likely outcome for free market systems. PMID:25383025

  4. 76 FR 2919 - Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental...

    Science.gov (United States)

    2011-01-18

    ... Protraction Diagram and Supplemental Official Outer Continental Shelf Block Diagrams AGENCY: Bureau of Ocean... American Datum of 1983 (NAD 83) Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental Shelf Block Diagrams. SUMMARY: Notice is hereby given that effective with...

  5. Detection of ancestry informative HLA alleles confirms the admixed origins of Japanese population.

    Science.gov (United States)

    Nakaoka, Hirofumi; Mitsunaga, Shigeki; Hosomichi, Kazuyoshi; Shyh-Yuh, Liou; Sawamoto, Taiji; Fujiwara, Tsutomu; Tsutsui, Naohisa; Suematsu, Koji; Shinagawa, Akira; Inoko, Hidetoshi; Inoue, Ituro

    2013-01-01

    The polymorphisms in the human leukocyte antigen (HLA) region are powerful tool for studying human evolutionary processes. We investigated genetic structure of Japanese by using five-locus HLA genotypes (HLA-A, -B, -C, -DRB1, and -DPB1) of 2,005 individuals from 10 regions of Japan. We found a significant level of population substructure in Japanese; particularly the differentiation between Okinawa Island and mainland Japanese. By using a plot of the principal component scores, we identified ancestry informative alleles associated with the underlying population substructure. We examined extent of linkage disequilibrium (LD) between pairs of HLA alleles on the haplotypes that were differentiated among regions. The LDs were strong and weak for pairs of HLA alleles characterized by low and high frequencies in Okinawa Island, respectively. The five-locus haplotypes whose alleles exhibit strong LD were unique to Japanese and South Korean, suggesting that these haplotypes had been recently derived from the Korean Peninsula. The alleles characterized by high frequency in Japanese compared to South Korean formed segmented three-locus haplotype that was commonly found in Aleuts, Eskimos, and North- and Meso-Americans but not observed in Korean and Chinese. The serologically equivalent haplotype was found in Orchid Island in Taiwan, Mongol, Siberia, and Arctic regions. It suggests that early Japanese who existed prior to the migration wave from the Korean Peninsula shared ancestry with northern Asian who moved to the New World via the Bering Strait land bridge. These results may support the admixture model for peopling of Japanese Archipelago. PMID:23577161

  6. Detection of ancestry informative HLA alleles confirms the admixed origins of Japanese population.

    Directory of Open Access Journals (Sweden)

    Hirofumi Nakaoka

    Full Text Available The polymorphisms in the human leukocyte antigen (HLA region are powerful tool for studying human evolutionary processes. We investigated genetic structure of Japanese by using five-locus HLA genotypes (HLA-A, -B, -C, -DRB1, and -DPB1 of 2,005 individuals from 10 regions of Japan. We found a significant level of population substructure in Japanese; particularly the differentiation between Okinawa Island and mainland Japanese. By using a plot of the principal component scores, we identified ancestry informative alleles associated with the underlying population substructure. We examined extent of linkage disequilibrium (LD between pairs of HLA alleles on the haplotypes that were differentiated among regions. The LDs were strong and weak for pairs of HLA alleles characterized by low and high frequencies in Okinawa Island, respectively. The five-locus haplotypes whose alleles exhibit strong LD were unique to Japanese and South Korean, suggesting that these haplotypes had been recently derived from the Korean Peninsula. The alleles characterized by high frequency in Japanese compared to South Korean formed segmented three-locus haplotype that was commonly found in Aleuts, Eskimos, and North- and Meso-Americans but not observed in Korean and Chinese. The serologically equivalent haplotype was found in Orchid Island in Taiwan, Mongol, Siberia, and Arctic regions. It suggests that early Japanese who existed prior to the migration wave from the Korean Peninsula shared ancestry with northern Asian who moved to the New World via the Bering Strait land bridge. These results may support the admixture model for peopling of Japanese Archipelago.

  7. ObStruct: a method to objectively analyse factors driving population structure using Bayesian ancestry profiles.

    Directory of Open Access Journals (Sweden)

    Velimir Gayevskiy

    Full Text Available Bayesian inference methods are extensively used to detect the presence of population structure given genetic data. The primary output of software implementing these methods are ancestry profiles of sampled individuals. While these profiles robustly partition the data into subgroups, currently there is no objective method to determine whether the fixed factor of interest (e.g. geographic origin correlates with inferred subgroups or not, and if so, which populations are driving this correlation. We present ObStruct, a novel tool to objectively analyse the nature of structure revealed in Bayesian ancestry profiles using established statistical methods. ObStruct evaluates the extent of structural similarity between sampled and inferred populations, tests the significance of population differentiation, provides information on the contribution of sampled and inferred populations to the observed structure and crucially determines whether the predetermined factor of interest correlates with inferred population structure. Analyses of simulated and experimental data highlight ObStruct's ability to objectively assess the nature of structure in populations. We show the method is capable of capturing an increase in the level of structure with increasing time since divergence between simulated populations. Further, we applied the method to a highly structured dataset of 1,484 humans from seven continents and a less structured dataset of 179 Saccharomyces cerevisiae from three regions in New Zealand. Our results show that ObStruct provides an objective metric to classify the degree, drivers and significance of inferred structure, as well as providing novel insights into the relationships between sampled populations, and adds a final step to the pipeline for population structure analyses.

  8. The influence of climate on age at menarche: Augmented with the influence of ancestry.

    Science.gov (United States)

    Sohn, Kitae

    2016-08-01

    Samples representative of South Korea, Indonesia, and Peninsular Malaysia were analyzed and the influence of climate on age at menarche was investigated. The sample size was 24,651 for Korea (birth years 1941-1992), for Indonesia 8331 (birth years 1944-1988) plus 20,519 (birth years 1978-1997), and 2842 for Peninsular Malaysia (birth years 1927-1968). Respondents recalled their age at menarche. The mean age at menarche was calculated for each birth year by country, and for Malaysia, additionally by ancestry. It has been found that mean ages at menarche for the early birth years were much younger in Indonesia than in Korea despite similar levels of socioeconomic conditions (proxied by GDP per capita). For example, for the birth year 1944, the mean age at menarche was 14.45 years for Indonesia and 16.19 years for Korea-a difference of 1.74 years. It was necessary to double the Korean GDP per capita to make the Korean mean age at menarche the same as the Indonesian one. Chinese and Malay women in Peninsular Malaysia were further analyzed, and the results provided indirect evidence that the difference between Korea and Indonesia was not due to ancestry differences. Results in multivariate settings provided consistent results. It has been concluded that climate exerts a significant influence on age at menarche because the relatively easy availability of food in the tropics increases energy intake while the absence of cold weather decreases energy expenditure on maintenance and activity. PMID:27369814

  9. A Method to Exploit the Structure of Genetic Ancestry Space to Enhance Case-Control Studies.

    Science.gov (United States)

    Bodea, Corneliu A; Neale, Benjamin M; Ripke, Stephan; Daly, Mark J; Devlin, Bernie; Roeder, Kathryn

    2016-05-01

    One goal of human genetics is to understand the genetic basis of disease, a challenge for diseases of complex inheritance because risk alleles are few relative to the vast set of benign variants. Risk variants are often sought by association studies in which allele frequencies in case subjects are contrasted with those from population-based samples used as control subjects. In an ideal world we would know population-level allele frequencies, releasing researchers to focus on case subjects. We argue this ideal is possible, at least theoretically, and we outline a path to achieving it in reality. If such a resource were to exist, it would yield ample savings and would facilitate the effective use of data repositories by removing administrative and technical barriers. We call this concept the Universal Control Repository Network (UNICORN), a means to perform association analyses without necessitating direct access to individual-level control data. Our approach to UNICORN uses existing genetic resources and various statistical tools to analyze these data, including hierarchical clustering with spectral analysis of ancestry; and empirical Bayesian analysis along with Gaussian spatial processes to estimate ancestry-specific allele frequencies. We demonstrate our approach using tens of thousands of control subjects from studies of Crohn disease, showing how it controls false positives, provides power similar to that achieved when all control data are directly accessible, and enhances power when control data are limiting or even imperfectly matched ancestrally. These results highlight how UNICORN can enable reliable, powerful, and convenient genetic association analyses without access to the individual-level data. PMID:27087321

  10. The Genetics of Bene Israel from India Reveals Both Substantial Jewish and Indian Ancestry

    Science.gov (United States)

    Davidson, Natalie R.; Billing-Ross, Paul; Dubrovsky, Maya; Campbell, Christopher L.; Oddoux, Carole; Friedman, Eitan; Atzmon, Gil; Halperin, Eran; Ostrer, Harry; Keinan, Alon

    2016-01-01

    The Bene Israel Jewish community from West India is a unique population whose history before the 18th century remains largely unknown. Bene Israel members consider themselves as descendants of Jews, yet the identity of Jewish ancestors and their arrival time to India are unknown, with speculations on arrival time varying between the 8th century BCE and the 6th century CE. Here, we characterize the genetic history of Bene Israel by collecting and genotyping 18 Bene Israel individuals. Combining with 486 individuals from 41 other Jewish, Indian and Pakistani populations, and additional individuals from worldwide populations, we conducted comprehensive genome-wide analyses based on FST, principal component analysis, ADMIXTURE, identity-by-descent sharing, admixture linkage disequilibrium decay, haplotype sharing and allele sharing autocorrelation decay, as well as contrasted patterns between the X chromosome and the autosomes. The genetics of Bene Israel individuals resemble local Indian populations, while at the same time constituting a clearly separated and unique population in India. They are unique among Indian and Pakistani populations we analyzed in sharing considerable genetic ancestry with other Jewish populations. Putting together the results from all analyses point to Bene Israel being an admixed population with both Jewish and Indian ancestry, with the genetic contribution of each of these ancestral populations being substantial. The admixture took place in the last millennium, about 19–33 generations ago. It involved Middle-Eastern Jews and was sex-biased, with more male Jewish and local female contribution. It was followed by a population bottleneck and high endogamy, which can lead to increased prevalence of recessive diseases in this population. This study provides an example of how genetic analysis advances our knowledge of human history in cases where other disciplines lack the relevant data to do so. PMID:27010569

  11. Identifying Barriers to Colonoscopy Screening for Nonadherent African American Participants in a Patient Navigation Intervention

    Science.gov (United States)

    Sly, Jamilia R.; Edwards, Tiffany; Shelton, Rachel C.; Jandorf, Lina

    2013-01-01

    African Americans have a higher rate of colorectal cancer (CRC) mortality than other racial/ethnic groups. This disparity is alarming given that CRC is largely preventable through the use of endoscopy (screening colonoscopy or sigmoidoscopy), yet rates of CRC screening among African Americans is suboptimal. Only 48.9% of African Americans are…

  12. Fractal Simulations of African Design in Pre-College Computing Education

    Science.gov (United States)

    Eglash, Ron; Krishnamoorthy, Mukkai; Sanchez, Jason; Woodbridge, Andrew

    2011-01-01

    This article describes the use of fractal simulations of African design in a high school computing class. Fractal patterns--repetitions of shape at multiple scales--are a common feature in many aspects of African design. In African architecture we often see circular houses grouped in circular complexes, or rectangular houses in rectangular…

  13. African American Faculty Expressing Concerns: Breaking the Silence at Predominantly White Research Oriented Universities

    Science.gov (United States)

    Ross, Henry H.; Edwards, Willie J.

    2016-01-01

    A Delphi method was used with a panel of 24 African American faculty employed at 43 predominantly white doctoral extensive universities to arrive at a group consensus on a list of concerns that African American faculty in general experienced or held. Using the Delphi method a panel of African American faculty initially worked from a list of eight…

  14. Intra-familial and ethnic effects on attitudinal and perceptual body image: a cohort of South African mother-daughter dyads

    Directory of Open Access Journals (Sweden)

    Goedecke Julia H

    2011-06-01

    Full Text Available Abstract Background International studies suggest ethnic differences in obesity prevalence may be due, in part, to differences in body image and body size dissatisfaction between groups. Further, there is evidence to suggest that there is a familial resemblance in body image between mothers and their younger (preadolescent daughters. This research was therefore conducted to specifically identify the extent to which family status (presented as mother-daughter resemblance and ethnicity impact on body image attitudes and perceptions of South African mothers and their pre-adolescent daughters. Methods Mother-daughter dyads (n = 201, 31% black, 37% mixed ancestry and 32% white answered questions regarding their body image perception (the way they saw their body size status, their body image ideals, and body image attitudes (body size dissatisfaction in particular, presented as the Feel-Ideal Difference [FID] index score. Mothers' and daughters' body image results were compared within dyads and across ethnic groups using repeated measures of ANOVA. Results Overall, body image resemblances exist between South African mothers and their pre-adolescent daughters. Mothers and daughters chose similarly weighted silhouettes to represent their body size ideals (p = 0.308, regardless of their ethnicity or body mass index (BMI. The FID index scores were similar between mothers and their daughters only after the confounding effects of maternal BMI were removed (p = 0.685. The silhouettes chosen to represent thinness were also similar between mothers and their daughters (p = 0.960 regardless of ethnicity and maternal BMI. On the other hand, the silhouettes chosen to represent fatness were similar (p = 0.342 between mothers and their daughters, only after the confounding effects of maternal BMI were removed. Lastly, mothers and their daughters chose similarly weighted silhouettes as engendering feelings of beauty, respect and happiness (p = 0.813; p = 0.615 and p

  15. Keeping African Masks Real

    Science.gov (United States)

    Waddington, Susan

    2012-01-01

    Art is a good place to learn about our multicultural planet, and African masks are prized throughout the world as powerfully expressive artistic images. Unfortunately, multicultural education, especially for young children, can perpetuate stereotypes. Masks taken out of context lose their meaning and the term "African masks" suggests that there is…

  16. Empowering African States

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China helps bring lasting peace and stability to Africa African think tanks expressed a high opinion of China’s role in helping build African peace and security at the first meeting of the China-Africa Think Tanks Forum. The

  17. African Literature as Celebration.

    Science.gov (United States)

    Achebe, Chinua

    1989-01-01

    Describes the Igbo tradition of "Mbari," a communal creative enterprise that celebrates the world and the life lived in it through art. Contrasts the cooperative, social dimension of pre-colonial African culture with the exclusion and denial of European colonialism, and sees new African literature again celebrating human presence and dignity. (AF)

  18. Continental mantle signature of Bushveld magmas and coeval diamonds.

    Science.gov (United States)

    Richardson, Stephen H; Shirey, Steven B

    2008-06-12

    The emplacement of the 2.05-billion-year-old Bushveld complex, the world's largest layered intrusion and platinum-group element (PGE) repository, is a singular event in the history of the Kaapvaal craton of southern Africa, one of Earth's earliest surviving continental nuclei. In the prevailing model for the complex's mineralization, the radiogenic strontium and osmium isotope signatures of Bushveld PGE ores are attributed to continental crustal contamination of the host magmas. The scale of the intrusion and lateral homogeneity of the PGE-enriched layers, however, have long been problematical for the crustal contamination model, given the typically heterogeneous nature of continental crust. Furthermore, the distribution of Bushveld magmatism matches that of seismically anomalous underlying mantle, implying significant interaction before emplacement in the crust. Mineral samples of the ancient 200-km-deep craton keel, encapsulated in macrodiamonds and entrained by proximal kimberlites, reveal the nature of continental mantle potentially incorporated by Bushveld magmas. Here we show that sulphide inclusions in approximately 2-billion-year-old diamonds from the 0.5-billion-year-old Venetia and 1.2-billion-year-old Premier kimberlites (on opposite sides of the complex) have initial osmium isotope ratios even more radiogenic than those of Bushveld sulphide ore minerals. Sulphide Re-Os and silicate Sm-Nd and Rb-Sr isotope compositions indicate that continental mantle harzburgite and eclogite components, in addition to the original convecting mantle magma, most probably contributed to the genesis of both the diamonds and the Bushveld complex. Coeval diamonds provide key evidence that the main source of Bushveld PGEs is the mantle rather than the crust. PMID:18548068

  19. Lake Van Drilling Project: A Long Continental Record in Eastern Turkey

    OpenAIRE

    T. Litt; S. Krastel; Örçen, S.; Karabiyikoglu, M.

    2007-01-01

    An international research group is proposing a new research initiative, the Lake Van Drilling Project ‘PaleoVan’ within the framework of the International Continental Scientific Drilling Program (ICDP). The project mainly aims at obtaining high-resolution paleoclimate records from lacustrine sediments, where biotic and abiotic parameters provide proxy climate data. Lake Van in Turkey has the potential to yield long continental records covering several glacial-interglacial cycles from annually...

  20. The East African rift system

    Science.gov (United States)

    Chorowicz, Jean

    2005-10-01

    This overview paper considers the East African rift system (EARS) as an intra-continental ridge system, comprising an axial rift. It describes the structural organization in three branches, the overall morphology, lithospheric cross-sections, the morphotectonics, the main tectonic features—with emphasis on the tension fractures—and volcanism in its relationships with the tectonics. The most characteristic features in the EARS are narrow elongate zones of thinned continental lithosphere related to asthenospheric intrusions in the upper mantle. This hidden part of the rift structure is expressed on the surface by thermal uplift of the rift shoulders. The graben valleys and basins are organized over a major failure in the lithospheric mantle, and in the crust comprise a major border fault, linked in depth to a low angle detachment fault, inducing asymmetric roll-over pattern, eventually accompanied by smaller normal faulting and tilted blocks. Considering the kinematics, divergent movements caused the continent to split along lines of preexisting lithospheric weaknesses marked by ancient tectonic patterns that focus the extensional strain. The hypothesis favored here is SE-ward relative divergent drifting of a not yet well individualized Somalian plate, a model in agreement with the existence of NW-striking transform and transfer zones. The East African rift system comprises a unique succession of graben basins linked and segmented by intracontinental transform, transfer and accommodation zones. In an attempt to make a point on the rift system evolution through time and space, it is clear that the role of plume impacts is determinant. The main phenomenon is formation of domes related to plume effect, weakening the lithosphere and, long after, failure inducing focused upper mantle thinning, asthenospheric intrusion and related thermal uplift of shoulders. The plume that had formed first at around 30 Ma was not in the Afar but likely in Lake Tana region (Ethiopia

  1. Continental Growth and the Sedimentary Record

    Science.gov (United States)

    Dhuime, B.; Hawkesworth, C. J.; Robinson, R. A. J.; Cawood, P. A.

    2014-12-01

    Detrital sedimentary rocks provide average samples of the continental crust formed at different times and in different places. Some materials are more susceptible to erosion and/or to preservation bias than others, and one issue is to understand how the compositions of a range of source rocks are then recorded in the sediments. Here we considered two different approaches to model the growth of the continental crust: (i) The variation of Nd isotopes in continental shales with different deposition ages, which requires a correction of the bias induced by preferential erosion of younger rocks through an erosion parameter usually referred to as 'K'. The determination of K, and the extent to which it varies in different erosion systems, thus have fundamental implications for the models of continental growth based on radiogenic isotopes in continental sediments. (ii) The variations in U-Pb, Hf and O isotopes in detrital zircons, from 'modern' sediments sampled worldwide. In this approach, O isotopes are used to screen 'hybrid' Hf model ages (i.e. ages resulting from mixing processes of crustal material from different ages) from Hf model ages that represent actual crust formation ages. These two approaches independently suggest that the continental crust has been generated continuously, but with a marked decrease in the continental growth rate at ~3 Ga. The >4 Ga to ~3 Ga period is characterised by relatively high net rates of continental growth (~3.0 km3.a-1), which are similar to the rates at which new crust is generated, and destroyed, at the present time. Net growth rates are much lower since 3 Ga (~0.8 km3.a-1), which may be attributed to higher rates of destruction of continental crust. The inflexion in the continental growth curve at ~3 Ga indicates a change in the way the crust was generated and preserved. This change may be linked to onset of subduction-driven plate tectonics and discrete subduction zones.

  2. "Sisters of Nia": A Social Justice Advocacy Intervention for School Counselors in Their Work with Adolescent African American Females

    Science.gov (United States)

    Grimes, Lee Edmondson; Haizlip, Breyan; Rogers, Tiffany; Brown, Kimberly D.

    2013-01-01

    Adolescent African American females face multiple obstacles that hinder their educational success. High school completion and college attendance rates remain lower for African American females than those for other racial and gender groups, while pregnancy rates for African American teens are higher. Group work holds promise for meeting the…

  3. The quality turn in South Africa: insights from a comprehensive investigation into the food quality behaviours, perceptions and knowledge of South African consumers with a focus on middle and upper socioeconomic groups

    OpenAIRE

    Vermeulen, Hester; Bienabe, Estelle

    2010-01-01

    Internationally, alternative food quality movements have given rise to a quality turn from the mass consumption model toward an increasing qualitative differentiation of products and demand (Allaire, 2002). While food quality trends and their implications have been widely analyzed internationally, little has been written on the local quality dynamics in South Africa, a country with clear dualistic socio-economic features. This paper aims to contribute to the understanding of South African con...

  4. African American Women’s Limited Knowledge and Experiences with Genetic Counseling for Hereditary Breast Cancer

    OpenAIRE

    Sheppard, Vanessa B.; Graves, Kristi D.; Christopher, Juleen; Hurtado-de-Mendoza, Alejandra; Talley, Costellia; Williams, Karen Patricia

    2013-01-01

    Genetic counseling and testing for hereditary breast cancer have the potential benefit of early detection and early interventions in African American women. However, African American women have low use of these services compared to White women. We conducted two focus groups with African American women diagnosed with breast cancer (affected group, n=13) and women with at least one first-degree relative with breast/ovarian cancer (unaffected group, n= 8). A content analysis approach was employe...

  5. Ectomycorrhizal symbiosis of tropical African trees.

    Science.gov (United States)

    Bâ, Amadou M; Duponnois, Robin; Moyersoen, Bernard; Diédhiou, Abdala G

    2012-01-01

    The diversity, ecology and function of ectomycorrhizal (EM) fungi and ectomycorrhizas (ECMs) on tropical African tree species are reviewed here. While ECMs are the most frequent mycorrhizal type in temperate and boreal forests, they concern an economically and ecologically important minority of plants in African tropical forests. In these African tropical forests, ECMs are found mainly on caesalpionioid legumes, Sarcolaenaceae, Dipterocarpaceae, Asterpeiaceae, Phyllantaceae, Sapotaceae, Papilionoideae, Gnetaceae and Proteaceae, and distributed in open, gallery and rainforests of the Guineo-Congolian basin, Zambezian Miombo woodlands of East and South-Central Africa and Sudanian savannah woodlands of the sub-sahara. Overall, EM status was confirmed in 93 (26%) among 354 tree species belonging to EM genera. In addition, 195 fungal taxa were identified using morphological descriptions and sequencing of the ML5/ML6 fragment of sporocarps and ECMs from West Africa. Analyses of the belowground EM fungal communities mostly based on fungal internal transcribed spacer sequences of ECMs from Continental Africa, Madagascar and the Seychelles also revealed more than 350 putative species of EM fungi belonging mainly to 18 phylogenetic lineages. As in temperate forests, the /russula-lactarius and /tomentella-thelephora lineages dominated EM fungal flora in tropical Africa. A low level of host preference and dominance of multi-host fungal taxa on different African adult tree species and their seedlings were revealed, suggesting a potential for the formation of common ectomycorrhizal networks. Moreover, the EM inoculum potential in terms of types and density of propagules (spores, sclerotia, EM root fragments and fragments of mycelia strands) in the soil allowed opportunistic root colonisation as well as long-term survival in the soil during the dry season. These are important characteristics when choosing an EM fungus for field application. In this respect, Thelephoroid fungal sp

  6. Mesoproterozoic Continental Arc Type Granite in the Central Tianshan Mountains: Zircon SHRIMP U-Pb Dating and Geochemical Analyses

    Institute of Scientific and Technical Information of China (English)

    YANG Tiannan; LI Jinyi; SUN Guihua; WANG Yanbin

    2008-01-01

    The Central Tianshan belt in northwestern China is a small Precambrian block located in the southern part of the Central Asia Orogenic Belt (CAOB), which is considered as "the most voluminous block of young continental crust in the world" that comprises numerous small continental blocks separated by Paleozoic magmatic arcs. The Precambrian basement of the central Tianshan Mountains is composed of volcanic rocks and associated volcano-sedimentary rocks that were intruded by granitic plutons. Geochemical analyses demonstrate that the granitic plutons and volcanic rocks were generated in the Andean-type active continental arc environment like today's Chile, and the zircon U-Pb SHRIMP dating indicates that they were developed at about 956 Ma, possibly corresponding to the subduction of the inferred Mozambique Ocean under the Baltic-African super-continent.

  7. African American Homeschooling Practices: Empirical Evidence

    Science.gov (United States)

    Mazama, Ama

    2016-01-01

    Despite a significant increase in scholarly interest for homeschooling, some of its most critical aspects, such as instructional daily practices, remain grossly understudied. This essay thus seeks to fill that void by presenting empirical evidence regarding the homeschooling practices of a specific group, African Americans. Most specifically, the…

  8. African Peacekeepers in Africa

    DEFF Research Database (Denmark)

    Emmanuel, Nikolas G.

    2015-01-01

    peacekeeping operations in the region. It is important to add that the international community has frequently tried to facilitate the deployment of African armed forces with aid and training. From this reality, the following study goes beyond the current literature by focusing on the international factors...... behind African participation in United Nations (UN) peacekeeping operations in Africa. In doing so, this research focuses on US military aid and foreign troop training from 2002 to 2012, and its impact on African deployments into UN peacekeeping missions in Africa. As can be expected, such third...

  9. Reading the African context

    OpenAIRE

    Musonda Bwalya

    2012-01-01

    There is so much alienation, pain and suffering in our today�s world. In this vein, African Christianity, a voice amongst many voices, should seek to be a transformational religion for the whole of life, affecting all facets of human life towards a fuller life of all in Africa. This article sought to highlight and point to some of the major societal challenges in the African context which African Christianity, as a life-affirming religion, should continue to embrace, re-embrace and engag...

  10. Capitalism and African business cultures

    OpenAIRE

    Taylor, Scott D.

    2014-01-01

    Scholars and practitioners once commonly linked 'African culture' to a distinctive 'African capitalism', at odds with genuine capitalism and the demands of modern business. Yet contemporary African business cultures reveal that a capitalist ethos has taken hold within both state and society. The success and visibility of an emergent, and celebrated, class of African big business reveals that business and profit are culturally acceptable. Existing theories of African capitalism are ill-equippe...

  11. The influence of genetic ancestry and ethnicity on breast cancer survival associated with genetic variation in the TGF-β-signaling pathway: The Breast Cancer Health Disparities Study

    OpenAIRE

    Slattery, Martha L.; Lundgreen, Abbie; Stern, Marianna C.; Hines, Lisa; Wolff, Roger K.; Giuliano, Anna R.; Baumgartner, Kathy B.; John, Esther M.

    2013-01-01

    The TGF-β signaling pathway regulates cellular proliferation and differentiation. We evaluated genetic variation in this pathway, its association with breast cancer survival, and survival differences by genetic ancestry and self-reported ethnicity.

  12. African American women's perceptions of cancer clinical trials

    OpenAIRE

    Haynes-Maslow, Lindsey; Godley, Paul; DiMartino, Lisa; White, Brandolyn; Odom, Janice; Richmond, Alan; Carpenter, William

    2014-01-01

    Cancer clinical trials are important for resolving cancer health disparities for several reasons; however, clinical trial participation among African Americans is significantly lower than Caucasians. This study engaged focus groups of 82 female African American cancer survivors or cancer caregivers, including those in better resourced, more urban areas and less resourced, more rural areas. Informed by an integrated conceptual model, the focus groups examined perceptions of cancer clinical tri...

  13. 雅加达非华裔大学生中文学习动机调查 JAKARTA NON-CHINESE ANCESTRY INDONESIAN STUDENTSMOTIVATION OF CHINESE STUDYING

    OpenAIRE

    Fu Ruomei; Huang Yan; Ye Mei

    2011-01-01

    More and more non-Chinese ancestry Indonesian begin to learn Chinese,some of them even choose Chinese as their major in University.The survey of four major Chinese departments in Jakarta shows that intrinsic motivation is the most important motivation of Chinese studying. Interests and passion to Chinese language and culture encouraged the non-Chinese ancestry Indonesian students to study Chinese. To assist them overcome their difficulties in studying is very important for Chinese education i...

  14. 5-HTTLPR Polymorphism: Analysis in South African Autistic Individuals

    KAUST Repository

    Arieff, Zainunisha

    2010-06-01

    The serotonin transporter promoter length polymorphism (5-hydroxytryptamine transporter length polymorphism; 5-HTTLPR) has long been implicated in autism and other psychiatric disorders. The use of selective serotonin reuptake inhibitors (SSRIs) has a positive effect on treating some symptoms of autism. The effects of these drugs vary in individuals because of the presence of the S or L allele of 5-HTTLPR. Studies performed on various autistic populations have found different allele frequencies for the L and S alleles. Allele frequencies and genotypes of the South African autistic populations (African, mixed, and Caucasian) were compared with matching South African ethnic control populations. The *S/*S genotype was found to be highly significantly associated with all the South African autistic ethnic populations. In the South African African population the *S/*S genotype was present in 7 (33%) of the autistic individuals but in none of the control subjects, yielding infinitely large odds of developing autism. The odds of developing autism with the *S/*S genotype compared to the *L/*L genotype increased 10.15-fold in the South African mixed group and 2.74-fold in the South African Caucasian population. The allele frequency of the South African autistic population was also compared with studies of other autistic populations around the world, and highly significant differences were found with the Japanese, Korean, and Indian population groups. The difference was not significant for the French, German, Israeli, Portuguese, and American groups. This is the first South African study of autistic individuals of different ethnic backgrounds that shows significant differences in allele and genotype frequencies of 5-HTTLPR. The results of this study open new avenues for investigating the role of transmission of the L and S alleles in families with autism in South Africa.

  15. Geometries of hyperextended continental crust in northeastern continental brazilian margin: insights from potential field and seismic interpretation

    Science.gov (United States)

    Magalhães, José; Barbosa, José; Ribeiro, Vanessa; Oliveira, Jefferson; Filho, Osvaldo; Buarque, Bruno

    2016-04-01

    The study region encompasses a set of three basins located at Northeast Brazilian continental margin: Pernambuco (south sector), Paraíba and Natal platform (north sector). These basins were formed during the last stage of separation between South America and African plates during Cretaceous. The continental breakup in these regions occurred probably during the Middle-Upper Albian (~102 m.y). The adjacent basement rocks belong to Borborema Province (BP), which was formed due a complex superposition between Pre-Cambrian orogenic cycles. The structural framework of BP is dominated by large shear zones that divided this province in three main tectonic domains: South, Central and North. The Pernambuco Basin is located in the South Domain and the Paraíba and Natal platform basins are related to the Central Domain. The tectonic and magmatic evolution of the Pernambuco Basin was influenced by oblique rifting (~ 35° to rift axis) and a thermal anomaly probably caused by the Santa Helena hotspot. The north sector represents a continental shelf characterized by basement high with a narrow platform and an abrupt shelf break on transition to the abyssal plain. The continental platform break of this sector was parallel to the rift axis. In this way, we present a regional structural interpretation of these sectors of Brazilian rifted margin based on interpretation and 2D forward modeling of potential field and 2D seismic data. The magnetic maps (Reduction to magnetic pole and Analytic signal) revealed the influence of an alternating pattern of large narrow magnetic and non-magnetic lineaments, oriented NE-SW, E-W and NW-SE. In the Pernambuco Basin these lineaments (NE-SW and E-W) are related to shear zones in the hyperextended basement which is interpreted as a continuation of the granitic-gneissic and metasedimentary rocks of the South Domain of BP. The Paraíba and Natal platform basins show a slight change in the orientation of structures trending E-W (shear zones in

  16. The genetic legacy of Lonesome George survives: Giant tortoises with Pinta Island ancestry identified in Galápagos

    OpenAIRE

    Edwards, DL; Benavides, E; Garrick, RC; Gibbs, JP; Russello, MA; Dion, KB; Hyseni, C; Flanagan, JP; Tapia, W. (ed.); Caccone, A

    2013-01-01

    The death of Lonesome George, the last known purebred individual of Chelonoidis abingdoni native to Pinta Island, marked the extinction of one of 10 surviving giant tortoise species from the Galápagos Archipelago. Using a DNA reference dataset including historical C. abingdoni and >1600 living Volcano Wolf tortoise samples, a site on Isabela Island known to harbor hybrid tortoises, we discovered 17 individuals with ancestry in C. abingdoni. These animals belong to various hybrid categories, i...

  17. Sex-specific Effects of Exercise Ancestry on Metabolic, Morphological, and Gene Expression Phenotypes in Multiple Generations of Mouse Offspring

    OpenAIRE

    Guth, Lisa M.; Andrew T. Ludlow; Witkowski, Sarah; Marshall, Mallory R.; Lima, Laila C. J.; Venezia, Andrew C.; Xiao, Tao; Lee, Mei-Ling Ting; Spangenburg, Espen E.; Roth, Stephen M.

    2013-01-01

    Early life and pre-conception environmental stimuli can affect adult health-related phenotypes. Exercise training is an environmental stimulus affecting many systems throughout the body and appears to alter offspring phenotypes. The aim of this study was to examine the influence of parental exercise training, or “exercise ancestry,” on morphological and metabolic phenotypes in two generations of mouse offspring. F0 C57BL/6 mice were exposed to voluntary exercise or sedentary lifestyle and bre...

  18. Empirical Selection of Informative Microsatellite Markers within Co-ancestry Pig Populations Is Required for Improving the Individual Assignment Efficiency

    OpenAIRE

    Y. H. Li; Chu, H. P.; Jiang, Y. N.; Lin, C.Y.; Li, S. H.; Li, K. T.; Weng, G. J.; Cheng, C. C.; Lu, D. J.; Ju, Y. T.

    2014-01-01

    The Lanyu is a miniature pig breed indigenous to Lanyu Island, Taiwan. It is distantly related to Asian and European pig breeds. It has been inbred to generate two breeds and crossed with Landrace and Duroc to produce two hybrids for laboratory use. Selecting sets of informative genetic markers to track the genetic qualities of laboratory animals and stud stock is an important function of genetic databases. For more than two decades, Lanyu derived breeds of common ancestry and crossbreeds hav...

  19. Paleoproterozoic Greenstone-Granite Belts in Northern Brazil and the Former Guyana Shield - West African Craton Province

    Directory of Open Access Journals (Sweden)

    Ian McReath

    2006-03-01

    Full Text Available The mainly meta-volcano-sedimentary Vila Nova Group and associated granites constitute separate belts, which formpart of a large paleoproterozoic (mainly rhyacian province in the Guyana Shield of which northern Brazil forms a part, andthe West African Craton. In Brazil the southwestern Serra do Ipitinga and Serra Tumucumaque-Serra do Navio belts have noobvious geometrical extensions in the Guyanas or Venezuela, and may represent deposits formed at penecontemporaneouspassive continental margins and ocean floor spreading centres. To the Northeast the Serra Lombarda-Tartarugalzinho andOiapoque belts are continuations of Guianese belts. In the former the igneous rocks have geochemical characteristics ofsuprasubduction environments. Belts in the Guyana Shield and West African Craton have many similar features. Themegaprovince evolved in a number of stages, which may have started at about 2.3 Ga, and continued with diminished activityafter 2.11 Ga. Both major juvenile additions and (possibly minor reworking of earlier crust contributed to the growth of theprovince. The major transcurrent deformation, responsible for the present structure of the belts, probably occurred duringthe later stages of evolution of the province, but metamorphism and deformation are registered even in the oldest rocks.

  20. Continental Shelf Boundary - Alaska NAD83

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Continental Shelf Boundaries (CSB) lines in ESRI shapefile format for the BOEM Alaska Region. The CSB defines the seaward limit of federally...

  1. Modeling the dynamics of continental shelf carbon.

    Science.gov (United States)

    Hofmann, Eileen E; Cahill, Bronwyn; Fennel, Katja; Friedrichs, Marjorie A M; Hyde, Kimberly; Lee, Cindy; Mannino, Antonio; Najjar, Raymond G; O'Reilly, John E; Wilkin, John; Xue, Jianhong

    2011-01-01

    Continental margin systems are important contributors to global nutrient and carbon budgets. Effort is needed to quantify this contribution and how it will be modified under changing patterns of climate and land use. Coupled models will be used to provide projections of future states of continental margin systems. Thus, it is appropriate to consider the limitations that impede the development of realistic models. Here, we provide an overview of the current state of modeling carbon cycling on continental margins as well as the processes and issues that provide the next challenges to such models. Our overview is done within the context of a coupled circulation-biogeochemical model developed for the northeastern North American continental shelf region. Particular choices of forcing and initial fields and process parameterizations are used to illustrate the consequences for simulated distributions, as revealed by comparisons to observations using quantitative statistical metrics. PMID:21329200

  2. Atlantic NAD 83 Continental Shelf Boundary (CSB)

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Continental Shelf Boundary (CSB) lines in ESRI shapefile format for the BOEM Atlantic Region. The CSB defines the seaward limit of federally...

  3. Rifting of Continental Interiors: Some New Geophysical Data and Interpretations

    Science.gov (United States)

    Keller, G. R.

    2005-12-01

    Rifting is one of the major processes that affect the evolution of the continents. This process sometimes leads to continental breakup and the formation of new oceans, but more often does not. This is presumably due to extension not progressing sufficiently to form a new plate margin resulting in a structure, which remains isolated in an intra-plate environment. The Southern Oklahoma aulacogen is such a feature, and the continental portion of the East African rift system may be a modern example. As more detailed geophysical and geological studies of rifts have become available in recent years, a complex picture of rift structure and evolution has emerged. Global patterns that reveal the connections between lithospheric structure (deep and shallow), magmatism (amount and style), amount of extension, uplift, and older structures remain elusive. However, our geophysical studies of modern and paleo rifts in North America, East Africa, and Europe makes it possible to make some general observations: 1). Magmatism in rifts is modest without the presence of a (pre-existing?) thermal anomaly in the mantle. 2). Magmatic modification of the crust takes many forms which probably depend on the nature of older structures present and the state of the lithosphere when rifting is initiated (i.e. cold vs. hot; fertility), 3) There is no clear relation between amount of extension and the amount of magmatic modification of the crust. 4) Brittle deformation in the upper crustal is complex, often asymmetrical and older features often play important roles in focusing deformation. However on a lithospheric scale, rift structure is usually symmetrical. 5) A better understanding of rift processes is emerging as we achieve higher levels of integration of a wide variety of geoscience data.

  4. Color, race, and genomic ancestry in Brazil: dialogues between anthropology and genetics.

    Science.gov (United States)

    Santos, Ricardo Ventura; Fry, Peter H; Monteiro, Simone; Maio, Marcos Chor; Rodrigues, José Carlos; Bastos-Rodrigues, Luciana; Pena, Sérgio D J

    2009-12-01

    In the contemporary world, "race" narratives are so multifaceted that at times, different views of the concept appear mutually incompatible. In recent decades biologists, especially geneticists, have repeatedly stated that the notion of race does not apply to the human species. On the other hand, social scientists claim that race is highly significant in cultural, historical, and socioeconomic terms because it molds everyday social relations and because it is a powerful motivator for social and political movements based on race differences. In this paper we present the results of an interdisciplinary research project incorporating approaches from genetics and anthropology. Our objective is to explore the interface between information about biology/genetics and perceptions about color/ race in Rio de Janeiro, Brazil. We argue that the data and interpretation of our research resonate far beyond the local level, stimulating discussion about methodological, theoretical, and political issues of wider national and international relevance. Topics addressed include the complex terminology of color/race classification in Brazil, perceptions about ancestry in the context of ideologies of Brazilian national identity, and the relationship between genetic information about the Brazilian population and a sociopolitical agenda that turns on questions of race and racism. PMID:20614657

  5. Genome-Wide DNA Methylation in Mixed Ancestry Individuals with Diabetes and Prediabetes from South Africa

    Science.gov (United States)

    Pheiffer, Carmen; Humphries, Stephen E.; Gamieldien, Junaid; Erasmus, Rajiv T.

    2016-01-01

    Aims. To conduct a genome-wide DNA methylation in individuals with type 2 diabetes, individuals with prediabetes, and control mixed ancestry individuals from South Africa. Methods. We used peripheral blood to perform genome-wide DNA methylation analysis in 3 individuals with screen detected diabetes, 3 individuals with prediabetes, and 3 individuals with normoglycaemia from the Bellville South Community, Cape Town, South Africa, who were age-, gender-, body mass index-, and duration of residency-matched. Methylated DNA immunoprecipitation (MeDIP) was performed by Arraystar Inc. (Rockville, MD, USA). Results. Hypermethylated DMRs were 1160 (81.97%) and 124 (43.20%), respectively, in individuals with diabetes and prediabetes when both were compared to subjects with normoglycaemia. Our data shows that genes related to the immune system, signal transduction, glucose transport, and pancreas development have altered DNA methylation in subjects with prediabetes and diabetes. Pathway analysis based on the functional analysis mapping of genes to KEGG pathways suggested that the linoleic acid metabolism and arachidonic acid metabolism pathways are hypomethylated in prediabetes and diabetes. Conclusions. Our study suggests that epigenetic changes are likely to be an early process that occurs before the onset of overt diabetes. Detailed analysis of DMRs that shows gradual methylation differences from control versus prediabetes to prediabetes versus diabetes in a larger sample size is required to confirm these findings.

  6. Mitochondrial control region genetic diversity and maternal ancestry of a Brangus-Ibage cattle populations

    Directory of Open Access Journals (Sweden)

    Luiz Ernani Henkes

    2005-03-01

    Full Text Available The genetic diversity of 277 nucleotides in the mitochondrial DNA control region (nt 15,964 to 16,240 in reference sequence was analyzed in crossbreed beef cattle (Brangus-Ibage, 5/8 Bos primigenius taurus x 3/8 Bos primigenius indicus as well as in some Nellore samples (B. p. indicus. Fifty-seven mutations were found in Brangus-Ibage comprising 18 haplotypes (haplotype diversity, h = 0.851 ± 0.041 and nucleotide diversity, ntd = 0.009 ± 0.006 and 66 in Nellore (h = 1.00 ± 0.27, ntd = 0.014 ± 0.012. These data indicated sequence identities of 99.6 and 92.1% between the B. p. taurus' reference sequence and Brangus-Ibage and Nellore, respectively. The comparison of our data with sequence data for 612 individuals recovered from GenBank showed a total of 205 haplotypes defined by 99 polymorphic sites. Most of the variability (53% was due to differentiation within breeds. The phylogenetic tree constructed using the neighbor-joining method showed clearly the well-known dichotomy between B. p. taurus and B. p. indicus. The Brangus-Ibage clustered with B. p. taurus lineages; however, the displacement of Nellore from B. p. indicus branch probably indicates a substantial B. p. taurus maternal ancestry in some Nellore samples (obtained from GenBank and reflects the primarily male-driven introduction of this breed in Brazil.

  7. Freshwater peat on the continental shelf

    Science.gov (United States)

    Emery, K.O.; Wigley, R.L.; Bartlett, A.S.; Rubin, M.; Barghoorn, E.S.

    1967-01-01

    Freshwater peats from the continental shelf off northeastern United States contain the same general pollen sequence as peats from ponds that are above sea level and that are of comparable radiocarbon ages. These peats indicate that during glacial times of low sea level terrestrial vegetation covered the region that is now the continental shelf in an unbroken extension from the adjacent land areas to the north and west.

  8. The evolution of African plant diversity

    OpenAIRE

    HansPeterLinder

    2014-01-01

    Sub-Saharan Africa includes some 45,000 plant species. The spatial patterns of this diversity have been well explored. We can group the species into a set of biogeographical regions (largely co-incident with regions defined for terrestrial vertebrate groups). Furthermore, we know that the diversity is unevenly distributed, with southern Africa (especially the south-western tip) disproportionally species rich, while the West African interior is disproportionally species poor. However, the ...

  9. The Continental Market Seen from the UK

    International Nuclear Information System (INIS)

    In this presentation, the Chairman of a French gas company (Elf) comments on the evolution of the Continental gas market from a British point of view. He first discusses the differences between the US, British and Continental gas markets, recalls the provisions of the European Gas Directive and states why a fully competitive system is a long-term prospect in Continental Europe. Seen from the UK, the provisions of the EU directive may appear modest. Due to the long transportation, British gas companies may find it hard to compete on the gas market of Continental Europe. When Inter connector, the gas pipeline connecting the gas markets in UK and the Continent, begins operation, there will be a flow of gas from the UK to the Continent according to already signed contracts. But there may be contractual flows both ways. Gas prices will level off between the UK and Northern Europe, at least for the industry. The continental markets will change gradually, the Gas Directive and the Inter connector will help the move towards a more competitive gas industry, but the fundamentals will not change: low gas prices for the next few years, competition between the big three exporters to Continental Europe, and long-term contracts that will extend beyond 2005

  10. Culturally sensitive instructional practices for African-American learners with disabilities.

    Science.gov (United States)

    Franklin, M E

    1992-01-01

    This article discusses the cultural and educational needs of African-American learners with disabilities. Six theoretical assumptions establish some basic suppositions about culturally and linguistically diverse learners and effective instructional practices. A review of the literature describes African-American cultural practices, interests, and cognitive styles; highlights the attitudes, perceptions, and instructional practices of effective teachers of African-American students; and includes patterns of teacher-student and peer-group interactions that promote high academic achievement among African-American learners. Recommendations include organizing teaching, learning, and performance in ways that are compatible with the social structure of African-American students with disabilities. PMID:1425853

  11. Atlas of prostate cancer heritability in European and African-American men pinpoints tissue-specific regulation

    Science.gov (United States)

    Gusev, Alexander; Shi, Huwenbo; Kichaev, Gleb; Pomerantz, Mark; Li, Fugen; Long, Henry W.; Ingles, Sue A.; Kittles, Rick A.; Strom, Sara S.; Rybicki, Benjamin A.; Nemesure, Barbara; Isaacs, William B.; Zheng, Wei; Pettaway, Curtis A.; Yeboah, Edward D.; Tettey, Yao; Biritwum, Richard B.; Adjei, Andrew A.; Tay, Evelyn; Truelove, Ann; Niwa, Shelley; Chokkalingam, Anand P.; John, Esther M.; Murphy, Adam B.; Signorello, Lisa B.; Carpten, John; Leske, M. Cristina; Wu, Suh-Yuh; Hennis, Anslem J. M.; Neslund-Dudas, Christine; Hsing, Ann W.; Chu, Lisa; Goodman, Phyllis J.; Klein, Eric A.; Witte, John S.; Casey, Graham; Kaggwa, Sam; Cook, Michael B.; Stram, Daniel O.; Blot, William J.; Eeles, Rosalind A.; Easton, Douglas; Kote-Jarai, ZSofia; Al Olama, Ali Amin; Benlloch, Sara; Muir, Kenneth; Giles, Graham G.; Southey, Melissa C.; Fitzgerald, Liesel M.; Gronberg, Henrik; Wiklund, Fredrik; Aly, Markus; Henderson, Brian E.; Schleutker, Johanna; Wahlfors, Tiina; Tammela, Teuvo L. J.; Nordestgaard, Børge G.; Key, Tim J.; Travis, Ruth C.; Neal, David E.; Donovan, Jenny L.; Hamdy, Freddie C.; Pharoah, Paul; Pashayan, Nora; Khaw, Kay-Tee; Stanford, Janet L.; Thibodeau, Stephen N.; McDonnell, Shannon K.; Schaid, Daniel J.; Maier, Christiane; Vogel, Walther; Luedeke, Manuel; Herkommer, Kathleen; Kibel, Adam S.; Cybulski, Cezary; Wokolorczyk, Dominika; Kluzniak, Wojciech; Cannon-Albright, Lisa; Teerlink, Craig; Brenner, Hermann; Dieffenbach, Aida K.; Arndt, Volker; Park, Jong Y.; Sellers, Thomas A.; Lin, Hui-Yi; Slavov, Chavdar; Kaneva, Radka; Mitev, Vanio; Batra, Jyotsna; Spurdle, Amanda; Clements, Judith A.; Teixeira, Manuel R.; Pandha, Hardev; Michael, Agnieszka; Paulo, Paula; Maia, Sofia; Kierzek, Andrzej; Cook, Margaret; Guy, Michelle; Govindasami, Koveela; Leongamornlert, Daniel; Sawyer, Emma J.; Wilkinson, Rosemary; Saunders, Edward J.; Tymrakiewicz, Malgorzata; Dadaev, Tokhir; Morgan, Angela; Fisher, Cyril; Hazel, Steve; Livni, Naomi; Lophatananon, Artitaya; Pedersen, John; Hopper, John L.; Adolfson, Jan; Stattin, Paer; Johansson, Jan-Erik; Cavalli-Bjoerkman, Carin; Karlsson, Ami; Broms, Michael; Auvinen, Anssi; Kujala, Paula; Maeaettaenen, Liisa; Murtola, Teemu; Taari, Kimmo; Weischer, Maren; Nielsen, Sune F.; Klarskov, Peter; Roder, Andreas; Iversen, Peter; Wallinder, Hans; Gustafsson, Sven; Cox, Angela; Brown, Paul; George, Anne; Marsden, Gemma; Lane, Athene; Davis, Michael; Zheng, Wei; Signorello, Lisa B.; Blot, William J.; Tillmans, Lori; Riska, Shaun; Wang, Liang; Rinckleb, Antje; Lubiski, Jan; Stegmaier, Christa; Pow-Sang, Julio; Park, Hyun; Radlein, Selina; Rincon, Maria; Haley, James; Zachariah, Babu; Kachakova, Darina; Popov, Elenko; Mitkova, Atanaska; Vlahova, Aleksandrina; Dikov, Tihomir; Christova, Svetlana; Heathcote, Peter; Wood, Glenn; Malone, Greg; Saunders, Pamela; Eckert, Allison; Yeadon, Trina; Kerr, Kris; Collins, Angus; Turner, Megan; Srinivasan, Srilakshmi; Kedda, Mary-Anne; Alexander, Kimberly; Omara, Tracy; Wu, Huihai; Henrique, Rui; Pinto, Pedro; Santos, Joana; Barros-Silva, Joao; Conti, David V.; Albanes, Demetrius; Berg, Christine; Berndt, Sonja I.; Campa, Daniele; Crawford, E. David; Diver, W. Ryan; Gapstur, Susan M.; Gaziano, J. Michael; Giovannucci, Edward; Hoover, Robert; Hunter, David J.; Johansson, Mattias; Kraft, Peter; Le Marchand, Loic; Lindström, Sara; Navarro, Carmen; Overvad, Kim; Riboli, Elio; Siddiq, Afshan; Stevens, Victoria L.; Trichopoulos, Dimitrios; Vineis, Paolo; Yeager, Meredith; Trynka, Gosia; Raychaudhuri, Soumya; Schumacher, Frederick R.; Price, Alkes L.; Freedman, Matthew L.; Haiman, Christopher A.; Pasaniuc, Bogdan

    2016-01-01

    Although genome-wide association studies have identified over 100 risk loci that explain ∼33% of familial risk for prostate cancer (PrCa), their functional effects on risk remain largely unknown. Here we use genotype data from 59,089 men of European and African American ancestries combined with cell-type-specific epigenetic data to build a genomic atlas of single-nucleotide polymorphism (SNP) heritability in PrCa. We find significant differences in heritability between variants in prostate-relevant epigenetic marks defined in normal versus tumour tissue as well as between tissue and cell lines. The majority of SNP heritability lies in regions marked by H3k27 acetylation in prostate adenoc7arcinoma cell line (LNCaP) or by DNaseI hypersensitive sites in cancer cell lines. We find a high degree of similarity between European and African American ancestries suggesting a similar genetic architecture from common variation underlying PrCa risk. Our findings showcase the power of integrating functional annotation with genetic data to understand the genetic basis of PrCa. PMID:27052111

  12. A genome-wide association study of serum uric acid in African Americans

    Directory of Open Access Journals (Sweden)

    Gerry Norman P

    2011-02-01

    Full Text Available Abstract Background Uric acid is the primary byproduct of purine metabolism. Hyperuricemia is associated with body mass index (BMI, sex, and multiple complex diseases including gout, hypertension (HTN, renal disease, and type 2 diabetes (T2D. Multiple genome-wide association studies (GWAS in individuals of European ancestry (EA have reported associations between serum uric acid levels (SUAL and specific genomic loci. The purposes of this study were: 1 to replicate major signals reported in EA populations; and 2 to use the weak LD pattern in African ancestry population to better localize (fine-map reported loci and 3 to explore the identification of novel findings cognizant of the moderate sample size. Methods African American (AA participants (n = 1,017 from the Howard University Family Study were included in this study. Genotyping was performed using the Affymetrix® Genome-wide Human SNP Array 6.0. Imputation was performed using MACH and the HapMap reference panels for CEU and YRI. A total of 2,400,542 single nucleotide polymorphisms (SNPs were assessed for association with serum uric acid under the additive genetic model with adjustment for age, sex, BMI, glomerular filtration rate, HTN, T2D, and the top two principal components identified in the assessment of admixture and population stratification. Results Four variants in the gene SLC2A9 achieved genome-wide significance for association with SUAL (p-values ranging from 8.88 × 10-9 to 1.38 × 10-9. Fine-mapping of the SLC2A9 signals identified a 263 kb interval of linkage disequilibrium in the HapMap CEU sample. This interval was reduced to 37 kb in our AA and the HapMap YRI samples. Conclusions The most strongly associated locus for SUAL in EA populations was also the most strongly associated locus in this AA sample. This finding provides evidence for the role of SLC2A9 in uric acid metabolism across human populations. Additionally, our findings demonstrate the utility of following-up EA

  13. Dismantling reified African culture through localised homosexualities in Uganda.

    Science.gov (United States)

    Nyanzi, Stella

    2013-01-01

    Uganda's Anti-Homosexuality Bill of 2009 aimed at protecting the cherished culture of the people against emergent threats to the traditional heterosexual family. The Bill's justification, however, lay in myopic imaginings of a homogenous African-ness and pedestrian oblivion to pluralities within African sexualities. This paper revisits the debate that homosexuality is 'un-African'. Rhetoric analysis of the Anti-Homosexuality Bill exposes how dominant discourses of law, medicine, religion, geography and culture reinforce the view that homosexuality is foreign to Africa. Based on ethnography in contemporary Uganda, I explore how self-identified same-sex-loving individuals simultaneously claim their African-ness and their homosexuality. Their strategies include ethnic belonging, membership to kinship structures, making connections with pre-colonial histories of homosexuality, civic participation in democratic processes, national identity, organising of lesbian, gay, bisexual, transgender, intersex and questioning support groups, language and nomenclature, visibility and voice in local communal activities, solidarity and adherence to cultural rituals. In present-day Uganda, same-sex-loving men, women and transgender people variously assert their African-ness. PMID:23767462

  14. 中国东北麻山杂岩晚泛非期变质的锆石SHRIMP年龄证据及全球大陆再造意义%The Mashan Complex: SHRIMP U-Pb zircon evidence for a Late Pan-African metamorphic event in NE China and its implication for global continental reconstructions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    中国东北地区佳木斯地块南部麻山杂岩正、副片麻岩7个样品的锆石SHRIMP年龄数据首次明确地表明,东北地区存在500Ma的晚泛非期高级变质作用事件。峰期麻粒岩相变质导致柳毛地区(502±10)Ma(2σ)深熔花岗岩的形成。正、副片麻岩变质年龄的一致性表明它们已在变质前发生了构造叠置。西麻山副片麻岩中含有在后期麻粒岩相变质过程中未重结晶的碎屑锆石,由此形成从协和一致的550Ma到弱不一致1900Ma的较大207Pb/206Pb年龄变化范围,表明其原岩具有从新元古代到中元古代-古元古代的年龄。柳毛地区变质的片麻状闪长岩中所含的古老锆石的207Pb/206Pb年龄为546~1460Ma表明,该闪长岩大约在1400Ma就位,并受到500Ma变质事件的影响,从而说明柳毛地区存在中元古代基底。然而,与以前的认识相反,麻山杂岩不存在具有太古宙基底的同位素证据。晚泛非期变质事件年龄的确定对重塑晚前寒武纪-显生宙早期麻山杂岩和佳木斯地块的古地理位置具有重要意义。根据目前获得的有关证据,认为佳木斯地块可能曾经位于冈瓦纳大陆北缘的华北克拉通附近。%SHRIMP U-Pb zircon dating of seven samples of ortho- andparagneisses obtained from the southern outcrop of the Mashan Complex provides the first conclusive evidence for a ~ 500 Ma Late Pan-African high-grade metamorphic event in northeastern China. Peak granulite facies metamorphism resulted in the production of local anatectic granite at Liumao and this gives a 206pb/238U age of (502 ± 10) Ma (2σ). There is no distinction between the metamorphic age of the ortho- and paragneisses, indicating that they were tectonically interleaved prior to metamorphism. Paragneisses from Ximashan contain evidence of detrital zircons that were not recrystallised during the granulite facies metamorphism. These show a spectrum of concordant to weakly

  15. A meta-analysis and genome-wide association study of platelet count and mean platelet volume in african americans.

    Directory of Open Access Journals (Sweden)

    Rehan Qayyum

    Full Text Available Several genetic variants associated with platelet count and mean platelet volume (MPV were recently reported in people of European ancestry. In this meta-analysis of 7 genome-wide association studies (GWAS enrolling African Americans, our aim was to identify novel genetic variants associated with platelet count and MPV. For all cohorts, GWAS analysis was performed using additive models after adjusting for age, sex, and population stratification. For both platelet phenotypes, meta-analyses were conducted using inverse-variance weighted fixed-effect models. Platelet aggregation assays in whole blood were performed in the participants of the GeneSTAR cohort. Genetic variants in ten independent regions were associated with platelet count (N = 16,388 with p<5×10(-8 of which 5 have not been associated with platelet count in previous GWAS. The novel genetic variants associated with platelet count were in the following regions (the most significant SNP, closest gene, and p-value: 6p22 (rs12526480, LRRC16A, p = 9.1×10(-9, 7q11 (rs13236689, CD36, p = 2.8×10(-9, 10q21 (rs7896518, JMJD1C, p = 2.3×10(-12, 11q13 (rs477895, BAD, p = 4.9×10(-8, and 20q13 (rs151361, SLMO2, p = 9.4×10(-9. Three of these loci (10q21, 11q13, and 20q13 were replicated in European Americans (N = 14,909 and one (11q13 in Hispanic Americans (N = 3,462. For MPV (N = 4,531, genetic variants in 3 regions were significant at p<5×10(-8, two of which were also associated with platelet count. Previously reported regions that were also significant in this study were 6p21, 6q23, 7q22, 12q24, and 19p13 for platelet count and 7q22, 17q11, and 19p13 for MPV. The most significant SNP in 1 region was also associated with ADP-induced maximal platelet aggregation in whole blood (12q24. Thus through a meta-analysis of GWAS enrolling African Americans, we have identified 5 novel regions associated with platelet count of which 3 were replicated in other ethnic

  16. Colorectal Cancer in African Americans: An Update.

    Science.gov (United States)

    Williams, Renee; White, Pascale; Nieto, Jose; Vieira, Dorice; Francois, Fritz; Hamilton, Frank

    2016-01-01

    This review is an update to the American College of Gastroenterology (ACG) Committee on Minority Affairs and Cultural Diversity's paper on colorectal cancer (CRC) in African Americans published in 2005. Over the past 10 years, the incidence and mortality rates of CRC in the United States has steadily declined. However, reductions have been strikingly much slower among African Americans who continue to have the highest rate of mortality and lowest survival when compared with all other racial groups. The reasons for the health disparities are multifactorial and encompass physician and patient barriers. Patient factors that contribute to disparities include poor knowledge of benefits of CRC screening, limited access to health care, insurance status along with fear and anxiety. Physician factors include lack of knowledge of screening guidelines along with disparate recommendations for screening. Earlier screening has been recommended as an effective strategy to decrease observed disparities; currently the ACG and American Society of Gastrointestinal Endoscopists recommend CRC screening in African Americans to begin at age 45. Despite the decline in CRC deaths in all racial and ethnic groups, there still exists a significant burden of CRC in African Americans, thus other strategies including educational outreach for health care providers and patients and the utilization of patient navigation systems emphasizing the importance of screening are necessary. These strategies have been piloted in both local communities and Statewide resulting in notable significant decreases in observed disparities. PMID:27467183

  17. "Mom Made Me Do It": The Role of Family in African Americans' Decisions to Enroll in Doctoral Education

    Science.gov (United States)

    McCallum, Carmen M.

    2016-01-01

    Large disparities exist among African Americans and other cultural groups in doctoral degree enrollment and degree attainment. To address this concern, scholars have focused on why African Americans do not pursue doctoral degrees. Although informative, this deficit perspective does not explain the factors that encourage African Americans to enroll…

  18. Contributions to knowledge of the continental margin of Uruguay. Uruguayan continental margin: Physiographic and seismic analysis

    International Nuclear Information System (INIS)

    This work is about the kind of continental margins such as a )Atlantic type passive margins which can be hard or soft b) An active or Pacific margins that because of the very frequent earthquakes develop a morphology dominated by tectonic processes. The Uruguayan continental margin belongs to a soft Atlantic margin

  19. African-Americans and Alzheimer's

    Science.gov (United States)

    ... Share Plus on Google Plus African-Americans and Alzheimer's alz.org | IHaveAlz Introduction 10 Warning Signs Brain ... African-Americans are at a higher risk for Alzheimer's disease. Many Americans dismiss the warning signs of ...

  20. Early B-cell differentiation in Merkel cell carcinomas: clues to cellular ancestry.

    Science.gov (United States)

    Zur Hausen, Axel; Rennspiess, Dorit; Winnepenninckx, Veronique; Speel, Ernst-Jan; Kurz, Anna Kordelia

    2013-08-15

    Merkel cell carcinoma (MCC) is a highly malignant neuroendocrine nonmelanoma skin cancer, which is associated with the Merkel cell polyoma virus (MCPyV). Recently, expression of the terminal deoxynucleotidyl transferase (TdT) and the paired box gene 5 (PAX 5) has been consistently reported in the majority of MCCs. We tested 21 MCCs for the expression of MCPyV, TdT, PAX5, IgG, IgM, IgA, kappa, and lambda by immunohistochemistry and assessed IgH and Igk rearrangement in all 21 MCCs. All of the MCCs revealed specific expression of PAX5 and 72.8% of the MCCs expressed TdT. In addition, most of the MCCs revealed specific expression of one or more Ig subclasses and kappa or lambda. One MCC did reveal monoclonal IgH and Igk rearrangement next to two other MCCs showing Igk rearrangement. As coexpression of TdT and PAX5 under physiologic circumstances is restricted to pro/pre- and pre-B cells we propose, on the basis of our results, that the cell of origin of MCCs is a pro/pre- or pre-B cell rather than the postmitotic Merkel cells. MCPyV infection and transformation of pro-/pre-B cells are likely to induce the expression of simple cytokeratins as has been shown for SV40 in other nonepithelial cells. This model of cellular ancestry of MCCs might impact therapy and possibly helps to understand why approximately 20% of MCCs are MCPyV-negative. PMID:23576560

  1. Massive and prolonged deep carbon emissions associated with continental rifting

    Science.gov (United States)

    Lee, Hyunwoo; Muirhead, James D.; Fischer, Tobias P.; Ebinger, Cynthia J.; Kattenhorn, Simon A.; Sharp, Zachary D.; Kianji, Gladys

    2016-02-01

    Carbon from Earth’s interior is thought to be released to the atmosphere mostly via degassing of CO2 from active volcanoes. CO2 can also escape along faults away from active volcanic centres, but such tectonic degassing is poorly constrained. Here we use measurements of diffuse soil CO2, combined with carbon isotopic analyses to quantify the flux of CO2 through fault systems away from active volcanoes in the East African Rift system. We find that about 4 Mt yr-1 of mantle-derived CO2 is released in the Magadi-Natron Basin, at the border between Kenya and Tanzania. Seismicity at depths of 15-30 km implies that extensional faults in this region may penetrate the lower crust. We therefore suggest that CO2 is transferred from upper-mantle or lower-crustal magma bodies along these deep faults. Extrapolation of our measurements to the entire Eastern rift of the rift system implies a CO2 flux on the order of tens of megatonnes per year, comparable to emissions from the entire mid-ocean ridge system of 53-97 Mt yr-1. We conclude that widespread continental rifting and super-continent breakup could produce massive, long-term CO2 emissions and contribute to prolonged greenhouse conditions like those of the Cretaceous.

  2. African Cultural Astronomy

    CERN Document Server

    Holbrook, Jarita C; Medupe, R. Thebe; Current Archaeoastronomy and Ethnoastronomy research in Africa

    2008-01-01

    Astronomy is the science of studying the sky using telescopes and light collectors such as photographic plates or CCD detectors. However, people have always studied the sky and continue to study the sky without the aid of instruments this is the realm of cultural astronomy. This is the first scholarly collection of articles focused on the cultural astronomy of Africans. It weaves together astronomy, anthropology, and Africa. The volume includes African myths and legends about the sky, alignments to celestial bodies found at archaeological sites and at places of worship, rock art with celestial imagery, and scientific thinking revealed in local astronomy traditions including ethnomathematics and the creation of calendars. Authors include astronomers Kim Malville, Johnson Urama, and Thebe Medupe; archaeologist Felix Chami, and geographer Michael Bonine, and many new authors. As an emerging subfield of cultural astronomy, African cultural astronomy researchers are focused on training students specifically for do...

  3. Genome-Wide Association Study to Identify Single Nucleotide Polymorphisms (SNPs) Associated With the Development of Erectile Dysfunction in African-American Men After Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Purpose: To identify single nucleotide polymorphisms (SNPs) associated with erectile dysfunction (ED) among African-American prostate cancer patients treated with external beam radiation therapy. Methods and Materials: A cohort of African-American prostate cancer patients treated with external beam radiation therapy was observed for the development of ED by use of the five-item Sexual Health Inventory for Men (SHIM) questionnaire. Final analysis included 27 cases (post-treatment SHIM score ≤7) and 52 control subjects (post-treatment SHIM score ≥16). A genome-wide association study was performed using approximately 909,000 SNPs genotyped on Affymetrix 6.0 arrays (Affymetrix, Santa Clara, CA). Results: We identified SNP rs2268363, located in the follicle-stimulating hormone receptor (FSHR) gene, as significantly associated with ED after correcting for multiple comparisons (unadjusted p = 5.46 x 10-8, Bonferroni p = 0.028). We identified four additional SNPs that tended toward a significant association with an unadjusted p value -6. Inference of population substructure showed that cases had a higher proportion of African ancestry than control subjects (77% vs. 60%, p = 0.005). A multivariate logistic regression model that incorporated estimated ancestry and four of the top-ranked SNPs was a more accurate classifier of ED than a model that included only clinical variables. Conclusions: To our knowledge, this is the first genome-wide association study to identify SNPs associated with adverse effects resulting from radiotherapy. It is important to note that the SNP that proved to be significantly associated with ED is located within a gene whose encoded product plays a role in male gonad development and function. Another key finding of this project is that the four SNPs most strongly associated with ED were specific to persons of African ancestry and would therefore not have been identified had a cohort of European ancestry been screened. This study demonstrates the

  4. African names for American plants

    NARCIS (Netherlands)

    Andel, van T.R.

    2015-01-01

    African slaves brought plant knowledge to the New World, sometimes applying it to related plants they found there and sometimes bringing Old World plants with them. By tracing the linguistic parallels between names for plants in African languages and in communities descended from African slaves, pie

  5. The Struggles over African Languages

    Science.gov (United States)

    Maseko, Pam; Vale, Peter

    2016-01-01

    In this interview, African Language expert Pam Maseko speaks of her own background and her first encounter with culture outside of her mother tongue, isiXhosa. A statistical breakdown of South African languages is provided as background. She discusses Western (originally missionary) codification of African languages and suggests that this approach…

  6. Androgen Metabolism Gene Polymorphisms, Associations with Prostate Cancer Risk and Pathological Characteristics: A Comparative Analysis between South African and Senegalese Men

    Directory of Open Access Journals (Sweden)

    Pedro Fernandez

    2012-01-01

    Full Text Available Prostate cancer is the most common cancer in men in developed countries and the leading cause of mortality in males in less developed countries. African ethnicity is one of the major risk factors for developing prostate cancer. Pathways involved in androgen metabolism have been implicated in the etiology of the disease. Analyses of clinical data and CYP3A4, CYP3A5, and SRD5A2 genotypes were performed in South African White (120 cases; 134 controls, Mixed Ancestry (207 cases; 167 controls, and Black (25 cases; 20 controls men, as well as in Senegalese men (86 cases; 300 controls. Senegalese men were diagnosed earlier with prostate cancer and had higher median PSA levels compared to South African men. Metastasis occurred more frequently in Senegalese men. Gene polymorphism frequencies differed significantly between South African and Senegalese men. The CYP3A4 rs2740574 polymorphism was associated with prostate cancer risk and tumor aggressiveness in South African men, after correction for population stratification, and the SRD5A2 rs523349 CG genotype was inversely associated with high-stage disease in Senegalese men. These data suggest that variants previously associated with prostate cancer in other populations may also affect prostate cancer risk in African men.

  7. African agricultural trade

    DEFF Research Database (Denmark)

    Jensen, Hans Grinsted; Sandrey, Ron

    2015-01-01

    This article starts with a profile of African agricultural trade. Using the pre-release version 9.2 of the GTAP database, we then show that the results for tariff elimination on intra-African trade are promising, but these tariff barriers are not as significant as the various trade-related barriers...... elimination, non-tariff barrier reductions and time in transit cost reductions are likely to be cumulative and would generate very large gains to Africa. The policy implications are clear: while cooperation will enhance the gains, much of the benefits will result from unilateral actions and regional...

  8. Insights into the Genetic Relationships and Breeding Patterns of the African Tea Germplasm Based on nSSR Markers and cpDNA Sequences.

    Science.gov (United States)

    Wambulwa, Moses C; Meegahakumbura, Muditha K; Kamunya, Samson; Muchugi, Alice; Möller, Michael; Liu, Jie; Xu, Jian-Chu; Ranjitkar, Sailesh; Li, De-Zhu; Gao, Lian-Ming

    2016-01-01

    Africa is one of the key centers of global tea production. Understanding the genetic diversity and relationships of cultivars of African tea is important for future targeted breeding efforts for new crop cultivars, specialty tea processing, and to guide germplasm conservation efforts. Despite the economic importance of tea in Africa, no research work has been done so far on its genetic diversity at a continental scale. Twenty-three nSSRs and three plastid DNA regions were used to investigate the genetic diversity, relationships, and breeding patterns of tea accessions collected from eight countries of Africa. A total of 280 African tea accessions generated 297 alleles with a mean of 12.91 alleles per locus and a genetic diversity (H S) estimate of 0.652. A STRUCTURE analysis suggested two main genetic groups of African tea accessions which corresponded well with the two tea types Camellia sinensis var. sinensis and C. sinensis var. assamica, respectively, as well as an admixed "mosaic" group whose individuals were defined as hybrids of F2 and BC generation with a high proportion of C. sinensis var. assamica being maternal parents. Accessions known to be C. sinensis var. assamica further separated into two groups representing the two major tea breeding centers corresponding to southern Africa (Tea Research Foundation of Central Africa, TRFCA), and East Africa (Tea Research Foundation of Kenya, TRFK). Tea accessions were shared among countries. African tea has relatively lower genetic diversity. C. sinensis var. assamica is the main tea type under cultivation and contributes more in tea breeding improvements in Africa. International germplasm exchange and movement among countries within Africa was confirmed. The clustering into two main breeding centers, TRFCA, and TRFK, suggested that some traits of C. sinensis var. assamica and their associated genes possibly underwent selection during geographic differentiation or local breeding preferences. This study represents

  9. Very recent African immigrants and unemployment in British Columbia

    OpenAIRE

    Rameshni, Farnaz

    2012-01-01

    Despite the provincial and federal governments focus on improving employment services through the Canada-British Columbia Immigration agreement, the unemployment rate among very recent African immigrants continues to remain the highest among other ethnic groups in Canada (StatCan, 2010). As such, this study looks into the various barriers faced by very recent African immigrants in finding employment in B.C., and addresses the problem through interviews with settlement agencies and a governmen...

  10. Influence of food availability on the diet and activity budget of two western lowland gorilla (Gorilla gorilla gorilla) groups of differing size in the Dzanga-Ndoki National Park, Central African Republic

    OpenAIRE

    Neba, Terence Fuh; Donati, Giuseppe; Todd, Angelique; Masi, Shelly

    2014-01-01

    Variation in food availability, body size and group size are known to influence primate diet and activity budgets. Here we report how seasonal food availability shapes the diet and activity patterns of two habituated western lowland gorilla (WLG) groups of differing size. WLGs are ripe fruit opportunists, showing dietary flexibility when preferred foods are scarce. However, as fruit can be rare/ patchily distributed, as intra-group feeding competition increases with group size, access to indi...

  11. Continental drift, organic evolution, and moral courage

    Science.gov (United States)

    Irving, Edward

    For the past 40 years or so there has been much discussion of the reasons why, even though there was substantial evidence for it, the continental drift hypothesis of Alfred Wegener and Wladimir Koppen was rejected in the first half of the 20th century. It was often derisively dismissed out of hand.On April 7, 1998, there was a note in Eos by David Stern that included a perceptive and amusing quotation from Teddy Bullard on the question, which has recently reached something of a culmination in an important new book, The Rejection of Continental Drift, by Naomi Oreskes and published by Oxford in 1999.

  12. Deepening African Ties

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chinese President Hu Jintao has just embarked on his state visits to eight African countries that will take him to both the northern and southern tips of the continent. This is his first trip abroad this year, and also his third visit to Africa

  13. East African institutions

    DEFF Research Database (Denmark)

    Nordby, Johannes Riber; Jacobsen, Katja

    For the past decade security in East Africa has gained focus internationally. However there is a growing ambition among African states to handle such issues by themselves, sometimes through regional institutions. This has been supported by many Western states but potential risks are often forgotten....

  14. African Women Writing Resistance

    Institute of Scientific and Technical Information of China (English)

    Jennifer Browdy de Hernandez; Pauline Dongala; Omotayo; Jolaosho; Anne Serafin

    2011-01-01

    AFRICAN Women Writing Resistance is the first transnational anthology to focus on women's strategies of resistance to the challenges they face in Africa today.The anthology brings together personal narratives,testimony,interviews,short stories,poetry,performance scripts,folktales and lyrics.

  15. African Women Writing Resistance

    Institute of Scientific and Technical Information of China (English)

    Jennifer; Browdy; de; Hernandez; Pauline; Dongala; Omotayo; Jolaosho; Anne; Serafin

    2011-01-01

    An Anthology of Contemporary Voices AFRICAN Women Writing Resistance is the first transnational anthology to focus on women’s strategies of resistance to the challenges they face in Africa today.The anthology brings together personal narratives,testimony,interviews, short stories,po-

  16. West African Antislavery Movements

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi; Pelckmans, Lotte

    2011-01-01

    In the context of liberalization of West African political regimes, the upsurge of audacious political entrepreneurs who want to end chattel slavery in their nation-state, resulted in the legal criminalisation of slavery in both Mauritania (2007) and Niger (2003) and in a proposal to revise the...... cultures (or ‘mentalities’) go hand in hand....

  17. Immunizations and African Americans

    Science.gov (United States)

    ... Program Grants Other Grants Planning and Evaluation Grantee Best Practices Black/African American Asthma Cancer Chronic Liver Disease ... 13 to 17 years who ever received the human papillomavirus (HPV) vaccination, 2014 - Males # doses ... 240-453-2882 Office of Minority Health Resource Center Toll Free: 1-800-444-6472 / Fax: ...

  18. The African Union

    DEFF Research Database (Denmark)

    Mandrup, Thomas; Mandrup, Bjørn

    2009-01-01

    . Moreover, the ‘African Security Architecture’, of which it is the central component, also includes sub-regional organisations to which responsibility is to be devolved for dealing with armed confl ict and other matters. These so-called Regional Economic Communities (RECs) are, likewise, constantly changing...

  19. African tick bite fever

    DEFF Research Database (Denmark)

    Johansen, Jakob Aaquist; Thybo, Søren

    2011-01-01

    The incident of spotted fever imported to Denmark is unknown. We present a classic case of African Tick Bite Fever (ATBF) to highlight a disease, which frequently infects wildlife enthusiasts and hunters on vacation in South Africa. ATBF has a good prognosis and is easily treated with doxycyclin...

  20. Managed European-Derived Honey Bee, Apis mellifera sspp, Colonies Reduce African-Matriline Honey Bee, A. m. scutellata, Drones at Regional Mating Congregations.

    Science.gov (United States)

    Mortensen, Ashley N; Ellis, James D

    2016-01-01

    African honey bees (Apis mellifera scutellata) dramatically changed the South American beekeeping industry as they rapidly spread through the Americas following their introduction into Brazil. In the present study, we aimed to determine if the management of European-derived honey bees (A. mellifera sspp.) could reduce the relative abundance of African-matriline drones at regional mating sites known as drone congregation areas (DCAs). We collected 2,400 drones at six DCAs either 0.25 km or >2.8 km from managed European-derived honey bee apiaries. The maternal ancestry of each drone was determined by Bgl II enzyme digestion of an amplified portion of the mitochondrial Cytochrome b gene. Furthermore, sibship reconstruction via nuclear microsatellites was conducted for a subset of 1,200 drones to estimate the number of colonies contributing drones to each DCA. Results indicate that DCAs distant to managed European apiaries (>2.8 km) had significantly more African-matriline drones (34.33% of the collected drones had African mitochondrial DNA) than did DCAs close (0.25 km) to managed European apiaries (1.83% of the collected drones had African mitochondrial DNA). Furthermore, nuclear sibship reconstruction demonstrated that the reduction in the proportion of African matriline drones at DCAs near apiaries was not simply an increase in the number of European matriline drones at the DCAs but also the result of fewer African matriline colonies contributing drones to the DCAs. Our data demonstrate that the management of European honey bee colonies can dramatically influence the proportion of drones with African matrilines at nearby drone congregation areas, and would likely decreasing the probability that virgin European queens will mate with African drones at those drone congregation areas. PMID:27518068

  1. African Psychology: The Psychological Adjustment of African Women Living in New Zealand

    Directory of Open Access Journals (Sweden)

    Adelowo, Adesayo

    2015-11-01

    Full Text Available Social representation theory is a social psychological framework of concepts and ideas relevant to studying psychosocial phenomena in modern societies. It suggests that social psychological phenomenon and processes can only be properly understood when they are anchored in history, culture and macro social conditions. Therefore, social representations are carriers of collective memories of social groups which are adequate for shaping the present through the past; while using the past to meet the demands of the present, which enables social groups to continue through time. Social groups are distinct in terms of their understanding of social phenomenon and other forms of action which in turn constitute their identity. In this article, I present an African psychological framework which represents African people’s worldview. Further to this, is my experience as a doctoral student, exploring the psychological adjustment of African women living in New Zealand. I reflect on why the framework that I had used in my research were deemed inadequate to be used as psychological principles, because they did not correspond with a Western lens of understanding behaviour, actions and social reality. I conclude that the outcome of my study shows the reification and legitimization of Western psychology over African psychology. This article provides a possibility for a critical account of unequal social relations between Western psychology and Indigenous psychology, and exposes the issue of power and resistance embedded in the heart of social representation theories as it relates to psychology.

  2. Meta-Analysis of Genome-Wide Association Studies in African Americans Provides Insights into the Genetic Architecture of Type 2 Diabetes

    Science.gov (United States)

    Chen, Brian H.; Li, Jiang; Chen, Wei-Min; Guo, Xiuqing; Liu, Jiankang; Bielinski, Suzette J.; Yanek, Lisa R.; Nalls, Michael A.; Comeau, Mary E.; Rasmussen-Torvik, Laura J.; Jensen, Richard A.; Evans, Daniel S.; Sun, Yan V.; An, Ping; Patel, Sanjay R.; Lu, Yingchang; Long, Jirong; Armstrong, Loren L.; Wagenknecht, Lynne; Yang, Lingyao; Snively, Beverly M.; Palmer, Nicholette D.; Mudgal, Poorva; Langefeld, Carl D.; Keene, Keith L.; Freedman, Barry I.; Mychaleckyj, Josyf C.; Nayak, Uma; Raffel, Leslie J.; Goodarzi, Mark O.; Chen, Y-D Ida; Taylor, Herman A.; Correa, Adolfo; Sims, Mario; Couper, David; Pankow, James S.; Boerwinkle, Eric; Adeyemo, Adebowale; Doumatey, Ayo; Chen, Guanjie; Mathias, Rasika A.; Vaidya, Dhananjay; Singleton, Andrew B.; Zonderman, Alan B.; Igo, Robert P.; Sedor, John R.; Kabagambe, Edmond K.; Siscovick, David S.; McKnight, Barbara; Rice, Kenneth; Liu, Yongmei; Hsueh, Wen-Chi; Zhao, Wei; Bielak, Lawrence F.; Kraja, Aldi; Province, Michael A.; Bottinger, Erwin P.; Gottesman, Omri; Cai, Qiuyin; Zheng, Wei; Blot, William J.; Lowe, William L.; Pacheco, Jennifer A.; Crawford, Dana C.; Grundberg, Elin; Rich, Stephen S.; Hayes, M. Geoffrey; Shu, Xiao-Ou; Loos, Ruth J. F.; Borecki, Ingrid B.; Peyser, Patricia A.; Cummings, Steven R.; Psaty, Bruce M.; Fornage, Myriam; Iyengar, Sudha K.; Evans, Michele K.; Becker, Diane M.; Kao, W. H. Linda; Wilson, James G.; Rotter, Jerome I.; Sale, Michèle M.; Liu, Simin; Rotimi, Charles N.; Bowden, Donald W.

    2014-01-01

    Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15×10−94African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies. PMID:25102180

  3. Meta-analysis of genome-wide association studies in African Americans provides insights into the genetic architecture of type 2 diabetes.

    Directory of Open Access Journals (Sweden)

    Maggie C Y Ng

    2014-08-01

    Full Text Available Type 2 diabetes (T2D is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1 and two novel loci (HLA-B and INS-IGF2 at genome-wide significance (4.15 × 10(-94African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies.

  4. Ambient noise tomography of the East African Rift in Mozambique

    Science.gov (United States)

    Domingues, Ana; Silveira, Graça; Ferreira, Ana M. G.; Chang, Sung-Joon; Custódio, Susana; Fonseca, João F. B. D.

    2016-03-01

    Seismic ambient noise tomography is applied to central and southern Mozambique, located in the tip of the East African Rift (EAR). The deployment of MOZART seismic network, with a total of 30 broad-band stations continuously recording for 26 months, allowed us to carry out the first tomographic study of the crust under this region, which until now remained largely unexplored at this scale. From cross-correlations extracted from coherent noise we obtained Rayleigh wave group velocity dispersion curves for the period range 5-40 s. These dispersion relations were inverted to produce group velocity maps, and 1-D shear wave velocity profiles at selected points. High group velocities are observed at all periods on the eastern edge of the Kaapvaal and Zimbabwe cratons, in agreement with the findings of previous studies. Further east, a pronounced slow anomaly is observed in central and southern Mozambique, where the rifting between southern Africa and Antarctica created a passive margin in the Mesozoic, and further rifting is currently happening as a result of the southward propagation of the EAR. In this study, we also addressed the question concerning the nature of the crust (continental versus oceanic) in the Mozambique Coastal Plains (MCP), still in debate. Our data do not support previous suggestions that the MCP are floored by oceanic crust since a shallow Moho could not be detected, and we discuss an alternative explanation for its ocean-like magnetic signature. Our velocity maps suggest that the crystalline basement of the Zimbabwe craton may extend further east well into Mozambique underneath the sediment cover, contrary to what is usually assumed, while further south the Kaapval craton passes into slow rifted crust at the Lebombo monocline as expected. The sharp passage from fast crust to slow crust on the northern part of the study area coincides with the seismically active NNE-SSW Urema rift, while further south the Mazenga graben adopts an N-S direction

  5. Assessing sanitary mixtures in East African cities

    OpenAIRE

    Letema, S.C.

    2012-01-01

    The urbanisation of poverty and informality in East African cities poses a threat to environmental health, perpetuates social exclusion and inequalities, and creates service gaps (UN-Habitat, 2008). This makes conventional sanitation provision untenable citywide, giving rise to the emergence of sanitation mixtures. Sanitation mixtures have different scales, institutional arrangements, user groups, and rationalities for their establishment, location, and management. For assessing the performan...

  6. African Primary Care Research: Participatory action research

    OpenAIRE

    Bob Mash

    2014-01-01

    Abstract This article is part of the series on African primary care research and focuses on participatory action research. The article gives an overview of the emancipatory-critical research paradigm, the key characteristics and different types of participatory action research. Following this it describes in detail the methodological issues involved in professional participatory action research and running a cooperative inquiry group. The article is intended to help students with writing thei...

  7. Crustal structure of Precambrian terranes in the southern African subcontinent with implications for secular variation in crustal genesis

    Science.gov (United States)

    Kachingwe, Marsella; Nyblade, Andrew; Julià, Jordi

    2015-07-01

    New estimates of crustal thickness, Poisson's ratio and crustal shear wave velocity have been obtained for 39 stations in Angola, Botswana, the Democratic Republic of Congo, Malawi, Mozambique, Namibia, Rwanda, Tanzania and Zambia by modelling P-wave receiver functions using the H-κ stacking method and jointly inverting the receiver functions with Rayleigh-wave phase and group velocities. These estimates, combined with similar results from previous studies, have been examined for secular trends in Precambrian crustal structure within the southern African subcontinent. In both Archean and Proterozoic terranes we find similar Moho depths [38-39 ± 3 km SD (standard deviation)], crustal Poisson's ratio (0.26 ± 0.01 SD), mean crustal shear wave velocity (3.7 ± 0.1 km s-1 SD), and amounts of heterogeneity in the thickness of the mafic lower crust, as defined by shear wave velocities ≥4.0 km s-1. In addition, the amount of variability in these crustal parameters is similar within each individual age grouping as between age groupings. Thus, the results provide little evidence for secular variation in Precambrian crustal structure, including between Meso- and Neoarchean crust. This finding suggests that (1) continental crustal has been generated by similar processes since the Mesoarchean or (2) plate tectonic processes have reworked and modified the crust through time, erasing variations in structure resulting from crustal genesis.

  8. Elephant teeth from the atlantic continental shelf

    Science.gov (United States)

    Whitmore, F.C., Jr.; Emery, K.O.; Cooke, H.B.S.; Swift, D.J.P.

    1967-01-01

    Teeth of mastodons and mastodons have been recovered by fishermen from at least 40 sites on the continental shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, and relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25.000 years.

  9. Plate Tectonics and Continental Drift: Classroom Ideas.

    Science.gov (United States)

    Stout, Prentice K.

    1983-01-01

    Suggests various classroom studies related to plate tectonics and continental drift, including comments on and sources of resource materials useful in teaching the topics. A complete list of magazine articles on the topics from the Sawyer Marine Resource Collection may be obtained by contacting the author. (JN)

  10. Swell transformation across the continental shelf

    OpenAIRE

    Tinder, Cynthia Viernes

    2000-01-01

    A preliminary analysis of swell decay across the continental shelf was conducted using data from the SHOaling Waves EXperiment (SHOWEX). Six Datawell Directional Waverider buoys were deployed along a cross-shelf transect, offshore of Duck, North Carolina during an active hurricane season in the fall of 1999.

  11. Coordination: Southeast Continental Shelf studies. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, D.W.

    1981-02-01

    An overview of the Oceanograhic Program of Skidaway Institute of Oceanograhy is presented. Included are the current five year plan for studies of the Southeast Continental Shelf, a summary of research accomplishments, proposed research for 1981-1982, current status of the Savannah Navigational Light Tower, and a list of publications. (ACR)

  12. The Transnationalization of the Akan Religion: Religion and Identity among the U.S. African American Community

    Directory of Open Access Journals (Sweden)

    Pauline Guedj

    2015-01-01

    Full Text Available In 1965, Gus Dinizulu, an African American percussionist, traveled to Ghana with the dance company he was leading. There, he took the trip as an opportunity to explore his African roots and met Nana Oparebea, the Ghanaian chief-priestess of the Akonedi Shrine, one of the most famous shrine houses north of Accra. At the Akonedi Shrine, Nana Oparebea performed for Dinizulu a divination, during which she explained that his enslaved ancestors were parts of the Akan people of Ghana and gave him the mission to search for other African Americans who, like him, were of Ghanaian ancestries. She also offered him a set of altars, containing the spiritual forces of the deities revered in the Akonedi Shrine and asked him to import in the United States what was then labelled the Akan religion. Based on research led both in Ghana and in the United States, the aim of this paper will be to describe the process of diffusion, importation, transnationalization and indigenization of the Akan religion between West Africa and the East Coast of the United States. Focusing on ethnographic data, we will argue that this process can only be understood if it is placed in the context of African American identity formations. Therefore, we will show how in the context of globalization, religion and identity constructions are walking hand-in-hand, creating new discourses on hybridity and authenticity.

  13. Classical sickle beta-globin haplotypes exhibit a high degree of long-range haplotype similarity in African and Afro-Caribbean populations

    Directory of Open Access Journals (Sweden)

    Jallow Muminatou

    2007-08-01

    Full Text Available Abstract Background The sickle (βs mutation in the beta-globin gene (HBB occurs on five "classical" βs haplotype backgrounds in ethnic groups of African ancestry. Strong selection in favour of the βs allele – a consequence of protection from severe malarial infection afforded by heterozygotes – has been associated with a high degree of extended haplotype similarity. The relationship between classical βs haplotypes and long-range haplotype similarity may have both anthropological and clinical implications, but to date has not been explored. Here we evaluate the haplotype similarity of classical βs haplotypes over 400 kb in population samples from Jamaica, The Gambia, and among the Yoruba of Nigeria (Hapmap YRI. Results The most common βs sub-haplotype among Jamaicans and the Yoruba was the Benin haplotype, while in The Gambia the Senegal haplotype was observed most commonly. Both subtypes exhibited a high degree of long-range haplotype similarity extending across approximately 400 kb in all three populations. This long-range similarity was significantly greater than that seen for other haplotypes sampled in these populations (P s mutation. Conclusion Two different classical βs haplotypes, sampled from different populations, exhibit comparable and extensive long-range haplotype similarity and strong LD. This LD extends across the adjacent recombination hotspot, and is discernable at distances in excess of 400 kb. Although the multi-centric geographic distribution of βs haplotypes indicates strong subdivision among early Holocene sub-Saharan populations, we find no evidence that selective pressures imposed by falciparum malaria varied in intensity or timing between these subpopulations. Our observations also suggest that cis-acting loci, which may influence outcomes in sickle cell disease, could lie considerable distances away from β-globin.

  14. Dynamics of the continental margins

    Energy Technology Data Exchange (ETDEWEB)

    1990-11-01

    On 18--20 June 1990, over 70 oceanographers conducting research in the ocean margins of North America attended a workshop in Virginia Beach, Virginia. The purpose of the workshop was to provide the Department of Energy with recommendations for future research on the exchange of energy-related materials between the coastal and interior ocean and the relationship between the ocean margins and global change. The workshop was designed to optimize the interaction of scientists from specific research disciplines (biology, chemistry, physics and geology) as they developed hypotheses, research questions and topics and implementation plans. The participants were given few restraints on the research they proposed other than realistic time and monetary limits. The interdisciplinary structure of the meeting promoted lively discussion and creative research plans. The meeting was divided into four working groups based on lateral, vertical, air/sea and sediment/water processes. Working papers were prepared and distributed before the meeting. During the meeting the groups revised the papers and added recommendations that appear in this report, which was reviewed by an Executive Committee.

  15. Stakeholder Perspectives on Barriers for Healthy Living for Low-Income African American Families

    OpenAIRE

    Jones, Veronnie Faye; Rowland, Michael L.; Young, Linda; Atwood, Katherine; Thompson, Kirsten; Sterrett, Emma; Honaker, Sarah Morsbach; Joel E. Williams; Johnson, Knowlton; Davis, Deborah Winders

    2014-01-01

    Background: Childhood obesity is a growing problem for children in the United States, especially for children from low-income, African American families. Objective: The purpose of this qualitative study was to understand facilitators and barriers to engaging in healthy lifestyles faced by low-income African American children and their families. Methods: This qualitative study used semi-structured focus group interviews with eight African American children clinically identified as overwe...

  16. Prevalence and Severity of Symptoms in a Sample of African Americans and White Participants

    OpenAIRE

    Taneja, Indu; So, Suzanna; Stewart, Julian M.; Evans, Meredyth; Jason, Leonard A.

    2015-01-01

    According to the Centers for Disease Control and Prevention (2013), African Americans have a substantially greater prevalence of a range of health conditions when compared to other racial or ethnic groups. Many of these conditions have been attributed to the historical and contemporary social and economic disparities faced by the African American community. While many health conditions occur at a higher rate in African Americans, it is unclear whether there are specific symptom clusters that ...

  17. Developments and Microbiological applications in African foods: Emphasis on Nigerian Wara cheese

    OpenAIRE

    Raheem, Bamidele

    2006-01-01

    African indigenous foods have received limited research. Most of these indigenous foods are fermented and they form part of the rich nutritional culture of many groups in African countries. The industrialization and commercialisation of these indigenous African fermented foods should be preceded by a thorough scientific knowledge of their processing which can be vital in the elimination of hunger and poverty. This study highlighted emerging developments and the microbiology of cereal-based an...

  18. Tectonics and melting in intra-continental settings

    NARCIS (Netherlands)

    Gorczyk, Weronika; Vogt, Katharina

    2015-01-01

    Most of the geodynamic theories of deformation aswell asmetamorphismandmelting of continental lithosphere are concentrated on plate boundaries and are dominated by the effects of subduction upon deformation of the margins of continental lithospheric blocks. However, it is becoming increasingly appar

  19. Federal Outer Continental Shelf Oil and Gas Production Statistics

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — Federal Outer Continental Shelf Oil and Gas Production Statistics by month and summarized annually. Outer Continental Shelf consists of Gulf of Mexico, Pacific and...

  20. The macro- and megabenthic fauna on the continental shelf of the eastern Amundsen Sea, Antarctica

    OpenAIRE

    Linse, Katrin; Griffiths, Huw J.; Barnes, Dave KA; Brandt, Angelika; Davey, Niki; David, Bruno; Grave, Sammy De; d'Udekem d'Acoz, Cédric; Eléaume, Marc; Glover, Adrian G.; Lenaïg G. Hemery; Mah, Christopher; Martín-Ledo, Rafael; Munilla, Tomás; O'Loughlin, Mark

    2013-01-01

    In 2008 the BIOPEARL II expedition on board of RRS James Clark Ross sailed to the eastern Amundsen Sea Embayment and Pine Island Bay, one of the least studied Antarctic continental shelf regions due to its remoteness and ice cover. A total of 37 Agassiz trawls were deployed at depth transects along the continental and trough slopes. A total of 5469 specimens, belonging to 32 higher taxonomic groups and more than 270 species, were collected. Species richness per station varied from 1 to 55. Th...

  1. Admixture mapping of serum vitamin D and parathyroid hormone concentrations in the African American-Diabetes Heart Study.

    Science.gov (United States)

    Palmer, Nicholette D; Divers, Jasmin; Lu, Lingyi; Register, Thomas C; Carr, J Jeffrey; Hicks, Pamela J; Smith, S Carrie; Xu, Jianzhao; Judd, Suzanne E; Irvin, Marguerite R; Gutierrez, Orlando M; Bowden, Donald W; Wagenknecht, Lynne E; Langefeld, Carl D; Freedman, Barry I

    2016-06-01

    Vitamin D and intact parathyroid hormone (iPTH) concentrations differ between individuals of African and European descent and may play a role in observed racial differences in bone mineral density (BMD). These findings suggest that mapping by admixture linkage disequilibrium (MALD) may be informative for identifying genetic variants contributing to these ethnic disparities. Admixture mapping was performed for serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, vitamin D-binding protein (VDBP), bioavailable vitamin D, and iPTH concentrations and computed tomography measured thoracic and lumbar vertebral volumetric BMD in 552 unrelated African Americans with type 2 diabetes from the African American-Diabetes Heart Study. Genotyping was performed using a custom Illumina ancestry informative marker (AIM) panel. For each AIM, the probability of inheriting 0, 1, or 2 copies of a European-derived allele was determined. Non-parametric linkage analysis was performed by testing for association between each AIM using these probabilities among phenotypes, accounting for global ancestry, age, and gender. Fine-mapping of MALD peaks was facilitated by genome-wide association study (GWAS) data. VDBP levels were significantly linked in proximity to the protein coding locus (rs7689609, LOD=11.05). Two loci exhibited significant linkage signals for 1,25-dihydroxyvitamin D on 13q21.2 (rs1622710, LOD=3.20) and 12q13.2 (rs11171526, LOD=3.10). iPTH was significantly linked on 9q31.3 (rs7854368, LOD=3.14). Fine-mapping with GWAS data revealed significant known (rs7041 with VDBP, P=1.38×10(-82)) and novel (rs12741813 and rs10863774 with VDBP, P<6.43×10(-5)) loci with plausible biological roles. Admixture mapping in combination with fine-mapping has focused efforts to identify loci contributing to ethnic differences in vitamin D-related traits. PMID:27032714

  2. Replication of GWAS hits by race for breast and prostate cancers in European Americans and African Americans

    Directory of Open Access Journals (Sweden)

    Jill Suzanne Barnholtz-Sloan

    2011-07-01

    Full Text Available In this study, we assessed association of GWAS hits by race with adjustment for potential population stratification (PS in two large, diverse study populations; the Carolina Breast Cancer Study (CBCS (N total = 3693 individuals and the University of Pennsylvania Study of Clinical Outcomes, Risk and Ethnicity (SCORE (N total = 1135 individuals. In both study populations, 136 ancestry information markers and GWAS hits (CBCS: FGFR2, 8q24; SCORE: JAZF1, MSMB, 8q24 were genotyped. Principal component analysis was used to assess ancestral differences by race. Multivariable unconditional logistic regression was used to assess differences in cancer risk with and without adjustment for the first ancestral principal component (PC1 and for an interaction effect between PC1 and the GWAS hit (SNP of interest. PC1 explained 53.7% of the variance for CBCS and 49.5% of the variance for SCORE. European Americans and African Americans were similar in their ancestral structure between CBCS and SCORE and cases and controls were well matched by ancestry. In the CBCS European Americans, 9/11 SNPs were significant after PC1 adjustment, but after adjustment for the PC1 by SNP interaction effect, only one SNP remained significant (rs1219648 in FGFR2; for CBCS African Americans , 6/11 SNPs were significant after PC1 adjustment and after adjustment for the PC1 by SNP interaction effect, all 6 SNPs remained significant and an additional SNP now became significant. In the SCORE European Americans, 0/9 SNPs were significant after PC1 adjustment and no changes were seen after additional adjustment for the PC1 by SNP interaction effect; for SCORE African Americans , 2/9 SNPs were significant after PC1 adjustment and after adjustment for the PC1 by SNP interaction effect, only one SNP remained significant (rs16901979 at 8q24. We show that genetic associations by race are modified by interaction between individual SNPs and population stratification.

  3. Leadership in the African context

    Directory of Open Access Journals (Sweden)

    M. Masango

    2002-08-01

    Full Text Available The Western world has always viewed the African continent as plagued by corruption; dictatorship; military coups; rebellious leaders; greediness; misuse of power; and incompetent, politically unstable leaders - in effect, suspicious leaders who undermine their own democracies. This paper analyzes African leadership and its impact by concentrating on three historical eras, namely; the African Religious era; the Christian era, and the era of Globalization. These affected African leadership. In addition, many brilliant minds left the continent in search of greener pastures. A review of these three eras will help us understand how leadership shifted from African values into Western concepts. The role of missionaries lead African people to live with both an African and a Western concept of life. In spite of the above problems, our past leaders did their best in addressing the difficulties they faced during the three eras. African concepts of leadership were often regarded as barbaric and uncultured. Structures were evaluated by Western standards. Due to globalisation, African leaders, through programmes like NEPAD, are going back to basics, drawing on African concepts of unity among its leadership. Effectiveness or life-giving leadership is emerging and empowering villagers/communities in the continent. This type of leadership is innovative and has brought new hope for the continent.

  4. Proteomic-coupled-network analysis of T877A-androgen receptor interactomes can predict clinical prostate cancer outcomes between White (non-Hispanic and African-American groups.

    Directory of Open Access Journals (Sweden)

    Naif Zaman

    Full Text Available The androgen receptor (AR remains an important contributor to the neoplastic evolution of prostate cancer (CaP. CaP progression is linked to several somatic AR mutational changes that endow upon the AR dramatic gain-of-function properties. One of the most common somatic mutations identified is Thr877-to-Ala (T877A, located in the ligand-binding domain, that results in a receptor capable of promiscuous binding and activation by a variety of steroid hormones and ligands including estrogens, progestins, glucocorticoids, and several anti-androgens. In an attempt to further define somatic mutated AR gain-of-function properties, as a consequence of its promiscuous ligand binding, we undertook a proteomic/network analysis approach to characterize the protein interactome of the mutant T877A-AR in LNCaP cells under eight different ligand-specific treatments (dihydrotestosterone, mibolerone, R1881, testosterone, estradiol, progesterone, dexamethasone, and cyproterone acetate. In extending the analysis of our multi-ligand complexes of the mutant T877A-AR we observed significant enrichment of specific complexes between normal and primary prostatic tumors, which were furthermore correlated with known clinical outcomes. Further analysis of certain mutant T877A-AR complexes showed specific population preferences distinguishing primary prostatic disease between white (non-Hispanic vs. African-American males. Moreover, these cancer-related AR-protein complexes demonstrated predictive survival outcomes specific to CaP, and not for breast, lung, lymphoma or medulloblastoma cancers. Our study, by coupling data generated by our proteomics to network analysis of clinical samples, has helped to define real and novel biological pathways in complicated gain-of-function AR complex systems.

  5. The genetic structure and history of Africans and African Americans

    OpenAIRE

    Tishkoff, Sarah A; Reed, Floyd A; Friedlaender, Françoise R; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B.; Awomoyi, Agnes A; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T; Kotze, Maritha J.; Lema, Godfrey; Moore, Jason H.

    2009-01-01

    Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic p...

  6. Preface - 'Biogeochemistry-ecosystem interaction on changing continental margins in the Anthropocene'

    Science.gov (United States)

    Liu, K.-K.; Emeis, Kay-Christian; Levin, Lisa A.; Naqvi, Wajih; Roman, Michael

    2015-01-01

    This special issue is a product of Workshop 1 of IMBIZO III held in Goa, India in January 2013 (Bundy et al., 2013). This IMBIZO (a Zulu word for gathering) has been organized by IMBER (Integrated Marine Biogeochemistry and Ecosystem Research) biannually since 2008. It employs a format of three concurrent but interacting workshops designed to synthesize information on topical research areas in marine science. Workshop 1 addressed the issue, "Biogeochemistry-ecosystem interaction in changing continental margins," which belongs to the purview of the Continental Margins Working Group (CMWG), co-sponsored by IMBER and LOICZ (Land-Ocean Interaction in the Coastal Zone). As a way to explore the emerging issues that concern the CMWG, the workshop had attracted 25 talks and 18 posters that explored the following topics: Human impacts on continental margins

  7. Y-chromosomal variation in sub-Saharan Africa: insights into the history of Niger-Congo groups.

    Science.gov (United States)

    de Filippo, Cesare; Barbieri, Chiara; Whitten, Mark; Mpoloka, Sununguko Wata; Gunnarsdóttir, Ellen Drofn; Bostoen, Koen; Nyambe, Terry; Beyer, Klaus; Schreiber, Henning; de Knijff, Peter; Luiselli, Donata; Stoneking, Mark; Pakendorf, Brigitte

    2011-03-01

    Technological and cultural innovations as well as climate changes are thought to have influenced the diffusion of major language phyla in sub-Saharan Africa. The most widespread and the richest in diversity is the Niger-Congo phylum, thought to have originated in West Africa ∼ 10,000 years ago (ya). The expansion of Bantu languages (a family within the Niger-Congo phylum) ∼ 5,000 ya represents a major event in the past demography of the continent. Many previous studies on Y chromosomal variation in Africa associated the Bantu expansion with haplogroup E1b1a (and sometimes its sublineage E1b1a7). However, the distribution of these two lineages extends far beyond the area occupied nowadays by Bantu-speaking people, raising questions on the actual genetic structure behind this expansion. To address these issues, we directly genotyped 31 biallelic markers and 12 microsatellites on the Y chromosome in 1,195 individuals of African ancestry focusing on areas that were previously poorly characterized (Botswana, Burkina Faso, Democratic Republic of Congo, and Zambia). With the inclusion of published data, we analyzed 2,736 individuals from 26 groups representing all linguistic phyla and covering a large portion of sub-Saharan Africa. Within the Niger-Congo phylum, we ascertain for the first time differences in haplogroup composition between Bantu and non-Bantu groups via two markers (U174 and U175) on the background of haplogroup E1b1a (and E1b1a7), which were directly genotyped in our samples and for which genotypes were inferred from published data using linear discriminant analysis on short tandem repeat (STR) haplotypes. No reduction in STR diversity levels was found across the Bantu groups, suggesting the absence of serial founder effects. In addition, the homogeneity of haplogroup composition and pattern of haplotype sharing between Western and Eastern Bantu groups suggests that their expansion throughout sub-Saharan Africa reflects a rapid spread followed by

  8. Contributions to knowledge of the continental margin of Uruguay. Description of background samples in the continental margin of Uruguay

    International Nuclear Information System (INIS)

    This study provide data concerning of the background sediments of the continental margin of Uruguay. There were carried out different works with witnesses in order to extract various sediment samples from the continental shelf

  9. Steps to African Development

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The development of Africa is vital to the world’s sustainable development.However,African countries still face key challenges in achieving the meaningful expansion of their economies.At the High-Level Symposium on China-Africa Investment Cooperation in Xiamen,southeast China’s Fujian Province,held from September 8 to 10,Chen Deming,Minister of Commerce of China,elaborates on these challenges and sees

  10. Biofuels: The African experience

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo, L.A.; Nkolo, M. [German Agency for Technical Cooperation GTZ, Delegation Regionale des Eaux et Forets, Bertoua (Cameroon)

    2009-07-01

    In July 2006, the African Non-Petroleum Producers Association was formed in Senegal, Africa to develop alternative energy sources. It involved 13 of Africa's poorest nations, who joined forces to become global suppliers of biofuels, and some have set mandatory mixing of ethanol into gasoline. Although several biofuel production projects have been launched in western Africa, many of the new projects and plantations have not yet reached maturity due to the time lag between plantation and full-scale production, which is about 6 years. Major projects that could be producing significant quantities of biofuels in the next few years are not yet reflected in production statistics. Although ethanol is not yet being produced in large quantities in Africa, short-term opportunities exist. Countries in the South African Development Community are using molasses from the sugar can industry to produce ethanol. Biodiesel is also not currently produced on a significant scale in western Africa, but several other countries are gaining experience with cotton and palm oil resources, and Jatropha. Biomass residue also represents a large potential for all African countries involved in timber production. Unlike biodiesel production, land use conflicts are not an issue with biomass residue production.

  11. A multi-gene approach reveals a complex evolutionary history in the Cyanistes species group.

    Science.gov (United States)

    Illera, Juan Carlos; Koivula, Kari; Broggi, Juli; Päckert, Martin; Martens, Jochen; Kvist, Laura

    2011-10-01

    Quaternary climatic oscillations have been considered decisive in shaping much of the phylogeographic structure around the Mediterranean Basin. Within this paradigm, peripheral islands are usually considered as the endpoints of the colonization processes. Here, we use nuclear and mitochondrial markers to investigate the phylogeography of the blue tit complex (blue tit Cyanistes caeruleus, Canary blue tit C. teneriffae and azure tit C. cyanus), and assess the role of the Canary Islands for the geographic structuring of genetic variation. The Canary blue tit exhibits strong genetic differentiation within the Canary Islands and, in combination with other related continental species, provides an ideal model in which to examine recent differentiation within a closely related group of continental and oceanic island avian species. We analysed DNA sequences from 51 breeding populations and more than 400 individuals in the blue tit complex. Discrepancies in the nuclear and mitochondrial gene trees provided evidence of a complex evolutionary process around the Mediterranean Basin. Coalescent analyses revealed gene flow between C. caeruleus and C. teneriffae suggesting a dynamic process with multiple phases of colonization and geographic overlapping ranges. Microsatellite data indicated strong genetic differentiation among the Canary Islands and between the Canary archipelago and the close continental areas, indicating limited contemporary gene flow. Diversification of the blue tit complex is estimated to have started during the early Pliocene (≈ 5 Ma), coincident with the end of Messinian salinity crisis. Phylogenetic analyses indicated that the North African blue tit is derived from the Canary blue tits, a pattern is avian 'back colonization' that contrasts with more traditionally held views of islands being sinks rather than sources. PMID:21880092

  12. African American Women’s Perceptions and Experiences about Breastfeeding

    Directory of Open Access Journals (Sweden)

    Cecilia S Obeng

    2015-12-01

    Full Text Available There are health benefits to breastfeeding for both mothers and their children. The preventive health effects of breastfeeding continue into adulthood, lowering rate of various chronic illnesses. African American women, especially of lower socioeconomic status, are less likely to breastfeed in comparison to their racial and ethnic counterparts. The purpose of this study was to explore how African American women experience breastfeeding in the early stages of postpartum care. Two focus groups (N=20, 10 in each group were conducted with African American mothers. Results revealed that participants felt that there were health benefits to breastfeeding, and organizations such as WIC provided support. However, participants stated that lack of information, negative perceptions, and unforeseen circumstances were barriers to breastfeeding. This study proposes support and interventions for this group to increase breastfeeding among this population.

  13. Continental drift and climate change drive instability in insect assemblages

    Science.gov (United States)

    Li, Fengqing; Tierno de Figueroa, José Manuel; Lek, Sovan; Park, Young-Seuk

    2015-06-01

    Global change has already had observable effects on ecosystems worldwide, and the accelerated rate of global change is predicted in the future. However, the impacts of global change on the stability of biodiversity have not been systematically studied in terms of both large spatial (continental drift) and temporal (from the last inter-glacial period to the next century) scales. Therefore, we analyzed the current geographical distribution pattern of Plecoptera, a thermally sensitive insect group, and evaluated its stability when coping with global change across both space and time throughout the Mediterranean region—one of the first 25 global biodiversity hotspots. Regional biodiversity of Plecoptera reflected the geography in both the historical movements of continents and the current environmental conditions in the western Mediterranean region. The similarity of Plecoptera assemblages between areas in this region indicated that the uplift of new land and continental drift were the primary determinants of the stability of regional biodiversity. Our results revealed that climate change caused the biodiversity of Plecoptera to slowly diminish in the past and will cause remarkably accelerated biodiversity loss in the future. These findings support the theory that climate change has had its greatest impact on biodiversity over a long temporal scale.

  14. Continental drift and climate change drive instability in insect assemblages.

    Science.gov (United States)

    Li, Fengqing; Tierno de Figueroa, José Manuel; Lek, Sovan; Park, Young-Seuk

    2015-01-01

    Global change has already had observable effects on ecosystems worldwide, and the accelerated rate of global change is predicted in the future. However, the impacts of global change on the stability of biodiversity have not been systematically studied in terms of both large spatial (continental drift) and temporal (from the last inter-glacial period to the next century) scales. Therefore, we analyzed the current geographical distribution pattern of Plecoptera, a thermally sensitive insect group, and evaluated its stability when coping with global change across both space and time throughout the Mediterranean region--one of the first 25 global biodiversity hotspots. Regional biodiversity of Plecoptera reflected the geography in both the historical movements of continents and the current environmental conditions in the western Mediterranean region. The similarity of Plecoptera assemblages between areas in this region indicated that the uplift of new land and continental drift were the primary determinants of the stability of regional biodiversity. Our results revealed that climate change caused the biodiversity of Plecoptera to slowly diminish in the past and will cause remarkably accelerated biodiversity loss in the future. These findings support the theory that climate change has had its greatest impact on biodiversity over a long temporal scale. PMID:26081036

  15. Institution Building for African Regionalism

    OpenAIRE

    Khadiagala, Gilbert M.

    2011-01-01

    Since the 1960s, African states have embraced regional integration as a vital mechanism for political cooperation and for pooling resources to overcome problems of small and fragmented economies. In building meaningful institutions for regionalism, however, Africans have faced the challenges of reconciling the diversities of culture, geography, and politics. As a result, African regional institutions are characterized by multiple and competing mandates and weak institutionalization. This stud...

  16. Both serum 25-hydroxyvitamin D and calcium levels may increase the risk of incident prostate cancer in Caribbean men of African ancestry

    OpenAIRE

    Jackson, Maria D; Marshall K. Tulloch-Reid; Lindsay, Carole M; Smith, Garrett; Bennett, Franklyn I.; McFarlane-Anderson, Norma; Aiken, William; Coard, Kathleen C. M.

    2015-01-01

    Circulating 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with both higher and lower risk of prostate cancer (PCa), whereas elevated levels of circulating calcium has been related to higher risks. However, there are few studies that account for effects of both calcium and 25(OH)D concentrations on incident PCa in a black population. We examined these relationships in a case–control study of men 40–80 years old with newly diagnosed, histologically confirmed PCa in Jamaica, ...

  17. Article Molecular analysis of three FUT3 gene single nucleotide polymorphisms and their relationship with the lewis erythrocytary phenotype in a human population of japanese-ancestry living in Tomé Açu, a town in the Brazilian Amazon

    OpenAIRE

    Pablo Abdon da Costa Francez; Tereza Cristina de Oliveira Corvelo; Flávio Ricardo Leal da Silva; Sidney Emanuel Batista dos Santos

    2007-01-01

    The Lewis blood group system involves two major antigens, Leª and Le b. Their antigenic determinants are not primary gene products but are synthesized by the transfer of sugar subunits to a precursory chain by a specific enzyme which is the product of the FUT3 gene (Lewis gene). The presence of three FUT3 gene single nucleotide polymorphisms (SNPs) (59T > G; 508G > A and 1067T > A) was related to the Lewis phenotype of erythrocytes from 185 individuals of Japanese ancestry living in the town ...

  18. African-Americans and Heart Disease, Stroke

    Science.gov (United States)

    ... Pressure High Blood Pressure Tools & Resources Stroke More African-Americans and Heart Disease, Stroke Updated:Apr 18, ... of getting those diseases are even higher for African-Americans. The good news is, African-Americans can ...

  19. Chronic Liver Disease and African Americans

    Science.gov (United States)

    ... American > Chronic Liver Disease Chronic Liver Disease and African Americans Among African Americans, chronic liver disease is a ... white women. At a glance – Cancer Rates for African Americans (2008-2012) Cancer Incidence Rates per 100,000 – ...

  20. Young Africans Tackle Their Continent's Environmental Issues

    Science.gov (United States)

    Olwoch, Jane Mukarugwiza

    2008-11-01

    Young African Scientists Session at the Fourth International Geosphere-Biosphere Programme Congress; Cape Town, South Africa, 7 May 2008; Africa is often described as a unique and diverse continent. This is reflected in its biodiversity, economic and social circumstances, and diversity in culture and environment. The Young African Scientists (YAS) session at the International Geosphere-Biosphere Programme Congress was one of the congress's highlights. Global environmental change research in Africa was presented to an audience that included visiting international and national scientists, policy makers, and a group of schoolchildren. From the uniqueness of Africa's paleoclimate to the diversity and complexity of current and future impacts of environmental change on Africa, the session not only provided an overview of current projects but also highlighted the problems that are intertwined with poverty. This session was sponsored by the Global Change System for Analysis, Research, and Training (START).

  1. Towards a Classification of the African Acacias

    Directory of Open Access Journals (Sweden)

    J. H. Ross

    1973-09-01

    Full Text Available Some of the first attempts to subdivide the genus Acacia Mill, as a whole are discussed briefly. Bentham’s work, in which the subdivisions of the genus were for the first time given names, is considered and his two series into which the African species fall are reproduced. The characters employed by various workers to divide the African species into two main groups are mentioned and the advantages of using each of these characters for the first dichotomy in a key are discussed. Recent work on pollen morphology and seedling morphology is correlated with general morphology. A proposal put forward by Guinet to divide Acacia into three large genera on the basis of pollen morphology is briefly discussed. Certain modifications to Bentham's series Vulgares and Gummiferae are suggested.

  2. Weak interaction in the African Easterly Jet

    Directory of Open Access Journals (Sweden)

    A. Lenouo

    2005-07-01

    Full Text Available Low-frequency, African Easterlies Waves (AEW are examined as disturbances embedded in the mid-tropospheric easterly jet of the African low troposphere. The solution to the nonlinear vorticity equation relevant to the description of waves is sought in the form of triplet waves. The latest suggest a unified method to determine their kinetics characteristic and to explain the mechanism of energy exchange between their different modes. The period of energy interaction between different modes of the global wave is equal to 3.5 days when the wave packet is moving with a group velocity dependent on the mean basic flow. The effects of nonlinearity are also identified, and it is noted that the horizontal shears of mean flow, as well as the temporal variation of the amplitude wave functions, are the controlling factors.

    Keywords. Meteorology and atmospheric dynamics (Synoptic-scale meteorology; Tropical meteorology; Waves and tides

  3. Structure of continental rifts: Role of older features and magmatism

    Energy Technology Data Exchange (ETDEWEB)

    Keller, G.R. [Univ. of Texas, El Paso, TX (United States)

    1996-12-31

    Recent geological and geophysical studies in several continental rifts have begun to shed light on the details of the processes which govern the structural evolution of these important exploration targets. In Kenya and Tanzania, the classic East African rift has been the object of several investigations which reveal that its location follows the boundary (suture ?) between the Tanzanian craton (Archean) and Mozambiquan belt (Proterozoic), The Baikal rift also follows a similar boundary, and the Mid-continent rift of North America appears to do the same. Rifts themselves often act as zones of weakness which are reactivated by younger tectonic regimes. The classic North American example of this effect is the Eocambrian Southern Oklahoma aulacogen which was deformed to create the Anadarko basin and Wichita uplift in the late Paleozoic. The Central basin platform has a similar history although the original rift formed at {approximately}1,100Ma. Integration of geophysical data with petrologic and geochemical data from several rift zones has also provided a new picture of the nature and extent of magmatic modification of the crust. An interesting contradiction is that Phanerozoic rifts, except the Afar region, show little evidence for major magmatic modification of the crust whereas, at least in North America, many Precambrian rifts are associated with very large mafic bodies in the crust. The Kenya rift displays evidence for modification of the lower crust in a two-phase magmatic history, but upper crustal magmatic features are limited to local intrusions associated with volcanoes. In this rift, complex basement structure plays a much more important role than previously realized, and the geophysical signatures of basement structure and magmatism are easy to confuse. If this is also the case in other rifts, additional rift basins remain to be discovered.

  4. Structure of continental rifts: Role of older features and magmatism

    Energy Technology Data Exchange (ETDEWEB)

    Keller, G.R. (Univ. of Texas, El Paso, TX (United States))

    1996-01-01

    Recent geological and geophysical studies in several continental rifts have begun to shed light on the details of the processes which govern the structural evolution of these important exploration targets. In Kenya and Tanzania, the classic East African rift has been the object of several investigations which reveal that its location follows the boundary (suture ) between the Tanzanian craton (Archean) and Mozambiquan belt (Proterozoic), The Baikal rift also follows a similar boundary, and the Mid-continent rift of North America appears to do the same. Rifts themselves often act as zones of weakness which are reactivated by younger tectonic regimes. The classic North American example of this effect is the Eocambrian Southern Oklahoma aulacogen which was deformed to create the Anadarko basin and Wichita uplift in the late Paleozoic. The Central basin platform has a similar history although the original rift formed at [approximately]1,100Ma. Integration of geophysical data with petrologic and geochemical data from several rift zones has also provided a new picture of the nature and extent of magmatic modification of the crust. An interesting contradiction is that Phanerozoic rifts, except the Afar region, show little evidence for major magmatic modification of the crust whereas, at least in North America, many Precambrian rifts are associated with very large mafic bodies in the crust. The Kenya rift displays evidence for modification of the lower crust in a two-phase magmatic history, but upper crustal magmatic features are limited to local intrusions associated with volcanoes. In this rift, complex basement structure plays a much more important role than previously realized, and the geophysical signatures of basement structure and magmatism are easy to confuse. If this is also the case in other rifts, additional rift basins remain to be discovered.

  5. Regional magnetic anomaly constraints on continental rifting

    Science.gov (United States)

    Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

    1985-01-01

    Radially polarized MAGSAT anomalies of North and South America, Europe, Africa, India, Australia and Antarctica demonstrate remarkably detailed correlation of regional magnetic lithospheric sources across rifted margins when plotted on a reconstruction of Pangea. These major magnetic features apparently preserve their integrity until a superimposed metamorphoric event alters the magnitude and pattern of the anomalies. The longevity of continental scale magnetic anomalies contrasts markedly with that of regional gravity anomalies which tend to reflect predominantly isostatic adjustments associated with neo-tectonism. First observed as a result of NASA's magnetic satellite programs, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans. Accordingly, satellite magnetic observations provide a further tool for investigating continental drift to compliment other lines of evidence in paleoclimatology, paleontology, paleomagnetism, and studies of the radiometric ages and geometric fit of the continents.

  6. Strain weakening enables continental plate tectonics

    OpenAIRE

    Gueydan, Frédéric; Précigout, Jacques; Montesi, Laurent G.J.

    2014-01-01

    International audience Much debate exists concerning the strength distribution of the continental lithosphere, how it controls lithosphere-scale strain localization and hence enables plate tectonics. No rheological model proposed to date is comprehensive enough to describe both the weakness of plate boundary and rigid-like behaviour of plate interiors. Here we show that the duality of strength of the lithosphere corresponds to different stages of microstructural evolution. Geological const...

  7. Sustainable Offshore Wind Potential in Continental Portugal

    OpenAIRE

    Costa, P.; Simões, T. (Tânia); Estanqueiro, Ana

    2010-01-01

    This study intends to depict the availability of the sustainable offshore wind energy for Continental Portugal and identify the preliminary areas for developing offshore wind parks. Two scenarios were performed to distinct the different offshore wind turbine prototypes assembled by the manufactory energy sector – bottom fixed and floating models. The results achieved until now indicate that Portugal has a very large potential for offshore wind deployments ready to be exploited, especial...

  8. Corporate Governance Reforms in Continental Europe

    OpenAIRE

    Luca Enriques; Paolo Volpin

    2007-01-01

    The fundamental problem of corporate governance in the United States is to alleviate the conflict of interest between dispersed small shareowners and powerful controlling managers. The fundamental corporate governance in continental Europe and in most of the rest of the world is different. There, few listed companies are widely held. Instead, the typical firm in stock exchanges around the world has a dominant shareholder, usually an individual or a family, who controls the majority of the vot...

  9. Precipitation of Continental Origin over South America

    Science.gov (United States)

    Martinez-Agudelo, J. A.; Dominguez, F.

    2012-12-01

    The Amazon forest receives high amounts of moisture from the tropical Atlantic. A significant part of this moisture is returned back to the atmosphere by the forest, and further redistributed to the rest of the continent by the meridional flow imposed by the Andes. Thus, the land-atmosphere interaction between the Amazon forest and the large-scale flow affects not only the forest itself but also the downstream regions. We develop a method to quantify the precipitation of continental origin over South America, and identify the contribution that selected source regions make to continental precipitation. The average annual cycle of precipitation of continental origin for the five-year period 2000-2004 shows a band of high values aligned along the northwest-southeast direction, from southern Peru to northeastern Argentina. The lowest values of precipitation of continental origin occur upstream, over the northeastern coast of South America. Precipitation that originates as moisture from the Amazon forest shows maximum values over the western side of the Amazon, east of the Andes, especially over southern Peru. The Amazon forest also contributes to precipitation over La Plata River Basin (LPRB) and the Pacific coast of Colombia. During its dry season, up to 29.3% of the precipitation over LPRB originates as moisture from the Amazon forest. Throughout the year, the contributions to precipitation over LPRB by the Amazon forest and LPRB (recycled precipitation) are in the same range, but out of phase. The average contribution of the rest of the continent to precipitation over LPRB is smaller but of the same order as that of the Amazon and LPRB.

  10. Magmatic expressions of continental lithosphere removal

    OpenAIRE

    Wang, Huilin; Currie, Claire A.

    2015-01-01

    Gravitational lithosphere removal in continental interior has been inferred from various observations, including anomalous surface deflections and magmatism. We use numerical models and a simplified theoretical analysis to investigate how lithosphere removal can be recognized in the magmatic record. One style of removal is a Rayleigh-Taylor-type instability, where removal occurs through dripping. The associated magmatism depends on the lithosphere thermal structure. Four types of magmatism ar...

  11. African fossil tali: further multivariate morphometric studies.

    Science.gov (United States)

    Lisowski, F P; Albrecht, G H

    1976-07-01

    Analysis of measurements from the tali of 21 individual fossil primates from Africa shows that the specimens fall into five clearly defined groups. Accordingly, these specimens have been included as groups along with extant species in a subsequent canonical analysis thus allowing the fossils to play their part in the determination of the canonical separations. The results of this procedure show that the five fossil groups lie in a part of the canonical space not occupied by any extant African primate. Their positions are between the envelope of Asiatic apes (Hylobates and Pongo) and the envelope of African forms near the edge which contains Pan and Papio. One fossil group is so similar to Hylobates that its talus may have functioned in locomotion in a parallel manner. Others lie near to Pongo in directions proceeding towards Pan and Papio and it is possible that this similarity may indicate remnants of morphological adaptation for climbing in these fossils. At the same time, however, individual specimens are closer to one or another of the extant groups and this considerable spread suggests that the locomotor adaptations as evidenced by talar morphology, of the primate fauna in Africa, may have been very different from those of the present day. This would not the inconsistent with the different habitats, floras and non-primate faunas that may have characterized the East African scene at these earlier times. Particular fossils from Olduvai and Kromdraai that are supposed to be australopithecine and therefore bipeds, are confirmed (Oxnard, '72; Lisowski et al., '74) as being totally different from man in their talar morphology and essentially rather similar to the majority of the other fossil tali examined. PMID:961834

  12. West Africa - a safe haven for frogs? A sub-continental assessment of the chytrid fungus (Batrachochytrium dendrobatidis.

    Directory of Open Access Journals (Sweden)

    Johannes Penner

    Full Text Available A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd. While Bd has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West African amphibians (one caecilian and 61 anuran species for the presence of Bd. The samples originated from seven West African countries - Bénin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a variety of habitats, ranging from lowland rainforests to montane forests, montane grasslands to humid and dry lowland savannahs. The species investigated comprised various life-history strategies, but we focused particularly on aquatic and riparian species. We used diagnostic PCR to screen 656 specimen swabs and histology to analyse 137 specimen toe tips. All samples tested negative for Bd, including a widespread habitat generalist Hoplobatrachus occipitalis which is intensively traded on the West African food market and thus could be a potential dispersal agent for Bd. Continental fine-grained (30 arc seconds environmental niche models suggest that Bd should have a broad distribution across West Africa that includes most of the regions and habitats that we surveyed. The surprising apparent absence of Bd in West Africa indicates that the Dahomey Gap may have acted as a natural barrier. Herein we highlight the importance of this Bd-free region of the African continent - especially for the long-term conservation of several threatened species depending on fast flowing forest streams (Conraua alleni ("Vulnerable" and Petropedetes natator ("Near Threatened" as well as the "Critically Endangered" viviparous toad endemic to the montane grasslands of Mount Nimba (Nimbaphrynoides occidentalis.

  13. Perceived Fatherhood Roles and Parenting Behaviors among African American Teen Fathers

    Science.gov (United States)

    Paschal, Angelia M.; Lewis-Moss, Rhonda K.; Hsiao, Tracy

    2011-01-01

    Despite the growing body of research on the topic of adolescent parenthood, few studies have examined the perceptions and lived experiences of African American teen fathers. The primary aim of this study was to examine how this group defines and performs the father role. In-depth interviews were conducted with 30 African American fathers aged 14…

  14. Institutional Barriers to Participation in Adult Education among African Americans within Religious Institutions.

    Science.gov (United States)

    Isaac, Paulette; Rowland, Michael

    2002-01-01

    Examined institutional deterrents to participation in adult education among African American Christian church members. Focus group interview data highlighted six categories of deterrents: lack of relevance, programmatic, communication, individual/personal, instructional techniques, and interpersonal. Results suggest that African American Christian…

  15. Critical Race Theory: A Counternarrative of African American Male Medical Students Attending Predominately White Medical Schools

    Science.gov (United States)

    Morgan, Adrienne L.

    2013-01-01

    The history of African Americans seeking medical education in the United States is rooted in a legacy of racial segregation, cultural constructs, and legal doctrine that differs from other ethnic and racial groups. The disturbing results of this legacy are that while African Americans account for 12.9% of the U.S. population, they only account for…

  16. African Americans and Mathematics Outcomes on National Assessment of Educational Progress: Parental and Individual Influences

    Science.gov (United States)

    Noble, Richard, III; Morton, Crystal Hill

    2013-01-01

    This study investigated within group differences between African American female and male students who participated in the 2009 National Assessment of Educational Progress mathematics assessment. Using results from participating states, we compare average scale scores of African American students based on home regulatory environment and interest…

  17. Understanding the Disproportionately Low Marriage Rate among African Americans: An Amalgam of Sociological and Psychological Constraints

    Science.gov (United States)

    Chambers, Anthony L.; Kravitz, Aliza

    2011-01-01

    African Americans have the lowest marriage rate of any racial and ethnic group in America. Although the low marriage rate among African Americans has been largely examined through a sociological lens by documenting structural barriers, which has important policy implications, researchers have not sufficiently examined the psychological and…

  18. Writing Differences in Teacher Performance Assessments: An Investigation of African American Language and Edited American English

    Science.gov (United States)

    Szpara, Michelle Y.; Wylie, E. Caroline

    2008-01-01

    Differential performance results occur when a specific population subgroup achieves a passing rate which is significantly lower than that of the normative reference group. African Americans do less well, in general, on all types of assessments, including constructed-response tests. The present study examined the writing styles of African American…

  19. Perspectives on Child Abuse and Labour: Global Ethical Ideals Versus African Cultural Realities

    Science.gov (United States)

    Ajayi, A. O.; Torimiro, D. O.

    2004-01-01

    This article focuses on the global and African postures on the issues of child abuse and child labour. The global ethical ideals of the issues are characterized within their various theoretical perspectives while the African cultural realities are explored through the use of focus group discussion sessions, which were organized in six rural…

  20. Are CRIS Cluster Patterns Differentially Associated with African American Enculturation and Social Distance?

    Science.gov (United States)

    Chavez-Korell, Shannon; Vandiver, Beverly J.

    2012-01-01

    The authors examined whether Black racial identity cluster patterns, using Cross Racial Identity Scale (CRIS) scores, were differentially associated with preference for African American culture and social distance from various cultural groups. African American college students (N = 351) completed the CRIS, an enculturation scale, and a social…