Are medical and nonmedical uses of large-scale genomic markers conflating genetics and ‘race’?

Posted in Articles, Health/Medicine/Genetics, Media Archive, Politics/Public Policy on 2012-03-24 03:04Z by Steven

Are medical and nonmedical uses of large-scale genomic markers conflating genetics and ‘race’?

Nature Genetics
Volume 36, Number 11s (2004)
pages S43-S47
DOI: 10.1038/ng1439

Charles N. Rotimi, Director
Center for Research on Genomics and Global Health

“…with each birth and each death we alter the genetic attributes of human populations and drawing a line around an ephemeral entity like a human race is an exercise in futility and idiocy.” —Pat Shipman, The Evolution of Racism

We now have the tools to describe the pattern of genetic variation across the whole genome and its relationship to the history of human origins and the differential distribution of diseases across populations and geography. We can begin to dissect common complex diseases and devise new therapeutic strategies to reduce adverse drug reactions, a key public health problem ranking between the fourth and sixth leading cause of death in the US. At the social level, the new genomic tools can help us to better appreciate the fluidity of social identity, including ‘race’, ‘ethnicity’ and the more complex notion of ancestry. Challenges surrounding the design of large-scale genotyping projects such as the international HapMap initiative and their future applications illustrate the complexities and ambiguities associated with the use of group labels in genomic research. Depending on how we use this information, the potential exists to describe simultaneously our similarities and differences without reaffirming old prejudices…

…Genetic variation and social identity

To reap the full benefits of the Human Genome Project and spin-offs like the HapMap project, we must be willing to move beyond old and simplistic interpretations of differential frequencies of disease variants by poorly defined social proxies of genetic relatedness like ‘race’. We should allow the genome to teach us the extent of our evolutionary history without abbreviating it with preconceived notions of population boundaries and social identities. We must recognize that social identities are formed in various ways—ancestry, ethnic and tribal background, geopolitical boundaries, language, and other social and behavioral activities. Identities change over time and from one context to another. Their use as markers of ‘relatedness’ in genetic research without appreciation for how they were formed is likely to produce misleading information concerning the distribution of genetic variation.

We all have a common birthplace somewhere in Africa and this common origin is the reason why we share most of our genetic information. Our common history also explains why contemporary African populations have more genetic variation than younger human populations that migrated out of Africa 100,000 years ago to populate other parts of the world, carrying with them a subset of the existing genetic information.

Given this shared history, why do we interpret human genetic variation data as though our differences rise to the level of subspecies? Two facts are relevant: (i) as a result of different evolutionary forces, including natural selection, there are geographical patterns of genetic variations that correspond, for the most part, to continental origin; and (ii) observed patterns of geographical differences in genetic information do not correspond to our notion of social identities, including ‘race’ and ‘ethnicity’. In this regard, no matter what categorical framework is applied, we cannot consistently use genetics to define racial groups without classifying some human populations as exceptions. Our evolutionary history is a continuous process of combining the new with the old, and the end result is a mosaic that is modified with each birth and death. This is why the process of using genetics to define ‘race’ is like slicing soup: “You can cut wherever you want, but the soup stays mixed”.

How can we grasp the population structure of our species? I believe this requires universal awareness that genomic information cannot be used either to confirm or to refine old social, political and economic classifications such as ‘race’. In particular, we should understand the following points: (i) individuals in genetics studies may have membership in more than one biogeographical clusters; (ii) the borders of these clusters are not distinct; and (iii) population clusters are influenced by sampling strategies. For example, the inference drawn from a study with one or two African populations will probably be very different from that drawn from a study with 100 African populations sampled from north, east, west, central and south Africa. As Steve Olson observed, “Not only do all people have the same set of genes, but all groups of people also share the major variants of those genes. Geneticists have never found a genetic marker that is of one type in all the members of one large group and of a different type in all the members of another large group”50. Furthermore, because most alleles are widespread, genetic differences among human populations are the result of gradations in allele frequencies rather than distinctive diagnostic genotypes…

Read the entire perspective here.

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Changing the paradigm from ‘race’ to human genome variation

Posted in Articles, Health/Medicine/Genetics, Media Archive on 2012-03-24 02:33Z by Steven

Changing the paradigm from ‘race’ to human genome variation

Nature Genetics
Volume 36, Number 11s (2004)
pages S5-S7
DOI: 10.1038/ng1454

Charmaine D. M. Royal, Associate Research Professor
Institute for Genome Sciences & Policy; Department of African and African American Studies
Duke University

Georgia M. Dunston, Founding Director, National Human Genome Center
Howard University

Knowledge from the Human Genome Project and research on human genome variation increasingly challenges the applicability of the term ‘race’ to human population groups, raising questions about the validity of inferences made about ‘race’ in the biomedical and scientific literature. Despite the acknowledged contradictions in contemporary science, population-based genetic variation is continually used to explain differences in health between ‘racial’ and ‘ethnic’ groups. In this commentary we posit that resolution of apparent paradoxes in relating biology to ‘race’ and genetics requires thinking ‘outside of the box’.

Introduction to the state of the science

Knowledge gained from the Human Genome Project and research on human genome variation is forcing a paradigm shift in thinking about the construct of ‘race’, much like the process described by Thomas Kuhn in his renowned book, The Structure of Scientific Revolutions. Kuhn describes the paradigm shift in science as occurring when anomalous, scientific results cannot be explained by inadequate methods. With an accumulation of such anomalies, scientists must begin to consider that the paradigm or model of reality under which the hypotheses are tested has shifted and is no longer valid. Today, scientists are faced with this situation in genomics, where existing biological models or paradigms of ‘racial’ and ‘ethnic’ categorizations cannot accommodate the uniqueness of the individual and universality of humankind that is evident in new knowledge emerging from human genome sequence variation research and molecular anthropological research. The paradigms of human identity based on ‘races’ as biological constructs are being questioned in light of the preponderance of data on human genome sequence variation and reflect the need for a new explanatory framework and vision of humankind with different fundamental assumptions about biological groups that can accommodate new knowledge from a new generation of research.

Discourse on the validity of ‘racial’ categorization in humans is certainly not new and will perhaps continue for generations to come, taking on various forms as new scientific and nonscientific knowledge emerges. Shifts have occurred over time from a purely anthropological or biological debate to conversations about numerous psychosocial, societal, ethical and legal ramifications indicative of the undeniable applicability of the topic of ‘race’ to virtually every aspect of human existence.

This commentary describes the intellectual climate under which new information from human genome research is introduced into twenty-first-century biomedical science and society, new information that forces a more integrative construct of human biology and disease. The discordance between ‘race’ and human genome variation sets the stage for an analysis of the state of the science on human genome variation and ‘race’ and the relationship between genome variation and population differences in health and disease. The paper also provides a brief background for, and overview of, this Supplement to Nature Genetics

…As previously indicated, much of the current literature on genetics and health disparities emphasizes the potential dangers of connecting genetics with disparities, and relatively little research has been directed towards the potential of genomics to further understand health disparities in ways that can accomplish the US public health objectives of Healthy People 2010: a long and healthy life for all and the elimination of health disparities. Conditions are prime for the application of knowledge gained from research on the structure of DNA sequence variation in African and African Diaspora populations to probe the influence of gene-environment interactions in race- and ethnicity-based health disparities. With plans underway for the Translational Genomics Research in the African Diaspora initiative, the NHGC is positioned to lead the US and the global community with a large-scale, interdisciplinary project for human genome research in the African Diaspora. Translational Genomics Research in the African Diaspora will be a population-based resource for translational genomics in clinical research, which capitalizes on the evolutionary and migration history of Africans and the African Diaspora, and a resource for dissecting the contributions of gene-environment interactions (environment broadly defined to include psychosocial, cultural and other subjective factors) to disease susceptibility and response to medicines…

Read the entire commentary here.

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