Search

Human variation, including questions about race, have been central to biological anthropology since its emergence as a professional discipline in the early 20th century. More recently, genomic data have been used to address open questions about the nature and scope of human variation. Results from genome-wide association studies and commercially available direct-to-consumer genetic ancestry tests have also kindled scholarly debate about the relationship between genetics/genomics and race. Such discussions among scholars and other stakeholders, illustrates that there are still many open issues about how genomic data influence the ways that people think about and debate race and racism. Genetic ancestry remains particularly contentious because of a complicated history of race within anthropology and other human sciences. In this article, I provide a broad overview on understandings of race given the new discoveries in genetics/genomics and provide examples of how these types of data continue to impact social and legal understandings of race. Ultimately, given that a primary focus of biological anthropology is to query human experience from a biological perspective, it will remain critical that biological anthropologists uphold the anti-racist tradition of modern anthropology and diligently work to shape narratives about human difference.

Objectives From a genetic perspective, relatively little is known about how mass emigrations of African, European, and Asian peoples beginning in the 16th century affected Indigenous Caribbean populations. Therefore, we explored the impact of serial colonization on the genetic variation of the first Caribbean islanders. Materials and methods Sixty-four members of St. Vincent's Garifuna Community and 36 members of Trinidad's Santa Rosa First People's Community (FPC) of Arima were characterized for mitochondrial DNA and Y-chromosome diversity via direct sequencing and targeted SNP and STR genotyping. A subset of 32 Garifuna and 18 FPC participants were genotyped using the GenoChip 2.0 microarray. The resulting data were used to examine genetic diversity, admixture, and sex biased gene flow in the study communities. Results The Garifuna were most genetically comparable to African descendant populations, whereas the FPC were more similar to admixed American groups. Both communities also exhibited moderate frequencies of Indigenous American matrilines and patrilines. Autosomal SNP analysis indicated modest Indigenous American ancestry in these populations, while both showed varying degrees of African, European, South Asian, and East Asian ancestry, with patterns of sex-biased gene flow differing between the island communities. Discussion These patterns of genetic variation are consistent with historical records of migration, forced, or voluntary, and suggest that different migration events shaped the genetic make-up of each island community. This genomic study is the highest resolution analysis yet conducted with these communities, and provides a fuller understanding of the complex bio-histories of Indigenous Caribbean peoples in the Lesser Antilles.

Within genetic anthropology, mitochondrial DNA (mtDNA) has garnered a prominent if not enduring place within the anthropological toolkit. MtDNA has provided new and innovative perspectives on the emergence and dispersal of our species, interactions with extinct human species, and illuminated relationships between human groups. In this paper, I provide a brief overview of the major findings ascertained from mtDNA about human origins, human dispersal across the globe, interactions with other hominin species, and the more recent uses of mtDNA in direct to consumer ancestry tests. Relative to nuclear DNA, mtDNA is a small section of the genome and due to its inheritance pattern provides a limited resolution of population history and an individual's genetic ancestry. Consequently, some scholars dismiss mtDNA as insignificant due to the limited inferences that may be made using the locus. Regardless, mtDNA provides some useful insights to understanding how social, cultural, and environmental factors have shaped patterns of genetic variability. Furthermore, with regard to the experiences of historically marginalized groups, in particular those of African descent throughout the Americas, mtDNA has the potential to fill gaps in knowledge that would otherwise remain unknown. Within anthropological sciences, the value of this locus for understanding human experience is maximized when contextualized with complementary lines of evidence.

The study of human variation is central to both social and biomedical sciences, but social and biomedical scientists diverge in how variation is theorized and operationalized. Race is especially problematic because it is a cultural concept that contains implicit and explicit understandings of how collective bodies differ. In this moderately updated article, originally published in

The study of human variation is central to both social and biomedical sciences, but social and biomedical scientists diverge in how variation is theorized and operationalized. Race is especially problematic because it is a cultural concept that contains implicit and explicit understandings of how collective bodies differ. In this article, we propose an operationalization of race that addresses both racial experience and human biological diversity, placing them within the same ontological sphere. Furthermore, this approach can more effectively advance antiracist pedagogy and politics. We argue that human biological diversity does not have to be in opposition to constructivist notions of race. Rather, racial experience is emphasized as an embodied experience that is as real and as valid as biological variation. By focusing on both racial experience and biological diversity, it becomes more feasible to operationalize race to fruitfully inform the pedagogy and politics of antiracism. To do so, racial experience must be more broadly conceived and should not always equate to negative outcomes. With the recognition that racial experience has the potential to be something other than damaging, an antiracist anthropology can more effectively address issues pertaining to racial health disparities.

Regions on chromosome 8q24 harbor susceptibility alleles for multiple cancers including colorectal (region 3) and prostate cancer (regions 1–4). The objectives of the present study were (i) to test whether single-nucleotide polymorphisms (SNPs) in region 4 are associated with colorectal cancer (CRC) in European or African Americans; (ii) to test whether 8q24 SNPs previously shown to be associated with colorectal and prostate cancer also show association in our multiethnic series and (iii) to test for association between 100 ancestry informative markers (AIMs) and CRC in both the African American and European American cohorts. In total, we genotyped nine markers on 8q24 and 100 unlinked AIMs in 569 CRC cases and 439 controls (490 European Americans and 518 African Americans) obtained retrospectively from a hospital-based sample. We found rs7008482 in 8q24 region 4 to be significantly associated with CRC in European Americans (P = 0.03). Also in region 4, we found that a second SNP, rs16900305, trended toward association with CRC in African Americans. The rs6983267 in region 3, previously implicated in CRC risk, trended toward association with disease in European Americans but not in African Americans. Finally, none of the 100 AIMs tested for association reached statistical significance after correction for multiple hypothesis testing. In summary, these results are evidence that 8q24 region 4 contains novel CRC-associated alleles in European and African Americans.

Prostate cancer is a common complex disease that disproportionately affects men of African descent. Recently, several different common variants on chromosome 8q24 have been shown to be associated with prostate cancer in multiple studies and ethnic groups. The objective of this study was to confirm the association of 8q24 markers with prostate cancer in African Americans. We genotyped 24 markers along 8q24 and 80 unlinked ancestry informative markers in a hospital-based case-control sample of 1057 African American men (490 prostate cancer cases and 567 controls). Association analyses of 8q24 markers with prostate cancer risk were adjusted for both global and local 8q24 admixture stratification using estimates from ancestry informative markers. We report that rs7008482, which maps to the 8q24.13 region, is an additional independent prostate cancer risk variant (P = 5 × 10−4), and we also replicate the association of rs16901979 with prostate cancer (P = 0.002). Other published risk variants in the region such as rs1447295 and rs6983267 showed a similar direction and magnitude of effect, but were not significant in our population. Both rs7008482 and rs16901979 independently predicted risk and remained significant (P < 0.001) after controlling for each other. Our data combined with additional replications of 8q24 markers provide compelling support for multiple regions of risk for prostate cancer on 8q24.

In the USA, African American (AA) men are at higher risk of developing and dying from prostate cancer (Pca). Strong and replicable associations between prostate cancer risk and regions 1, 2, and 3 of 8q24 among cohorts of European ancestry have been found but few for those of African ancestry. Recently, we discovered in a study of AAs, a fourth region of Pca risk at 126 Mb of 8q24.13 surrounding SNP rs7008482. Region 4 is 2 Mb upstream of the other three regions on 8q24 and contains two interesting candidate genes for Pca risk. To further interrogate region 4, we performed fine-mapping within a 500-Kb region (126.1Mb-126.6Mb). SNPs were selected for fine-mapping of the region based on the following characteristics: tagging SNPs from Yoruba HAPMAP data and non-synonymous or potential regulatory SNPs. We genotyped 250 SNPs in 263 AA Pca cases and 562 AA healthy controls. A structured-association analysis taking into account African ancestry, (local 8q24 ancestry and genomic ancestry) revealed that several SNPs within two genes KIAA0196 and NSMCE2 were significantly associated with Pca risk. The majority of the associated SNPs were common and exhibited low to moderate risk which may contribute to high population attributable risk in African Americans. Among these, rs16900305, located in an intronic region of KIAA0196, exhibited the strongest association (P=0.0003). KIAA0196 has been shown to be over-expressed in clinical prostate carcinomas and in approximately 30% of hormone-refractory tumors. Our findings strongly support region 4 in 8q24.13 as a candidate locus influencing prostate cancer risk among African Americans. Given the two interesting genes in this region and strong associations in a high risk group for Pca, further attention to this region is warranted. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4725.