2B Genetic Ancestry, Racial Identity, and Health Disparities 10/6

Blumenback’s five races

Linnaeus and race

ancestry vs race

• race is a social construct that is related to but not synonymous with our ancestry or lineage

• it reflects laws and norms that interpret our ancestry and other factors to assign people to categories to rights and resources

  • one drop rule = if you have a sub-Saharan ancestor → Black

measures of ancestry

• genetic similarity (estimated from SNPs)

• social ancestry )genealogy, family lore)

measures of race

• racialized appearance (observed race)

• racial identity (census report, self-id)

how is human genetic variation social?

• contemporary genetic variation is not only dependent on “natural” processes

• clustering party determined by geographic boundaries (mountains, deserts, oceans) that historically hindered human contact

• also reflects social and political boundaries

  • wars, genocide, etc

limitations of current genetic approaches

• sampling decisions shape databases

  • not all databases can be generalizable because lacking specific information

• using continental labels reinscribes “race”

genetics is not neutral

• using a measure of genetic ancestry can be seen as less problematic

shifting norms about race

• one reason race is described as a social construct is because the names and numbers of categories that people have called “races” vary over time

• criteria for deciding who belongs in each group

what are some social boundaries to considering you being included in a “race”?

• social Normas draw abitrary boundaries as we interpret who counts as what and why

  • e.g. how far back should we go in our ancestry to be considered a part of that race

hypo descent

• e.g. one drop rule bc even one distinct ancestor is determined classification as Black

hyper descent

• blood quantum rules applied to American Indians and Alaska natives work in the opposite way with indigenous ancestry and gradually diluted as “mixing occurs”

translating ancestry to race

• social norms kept ancestry and racial identities more district with race reflecting social experience

• growing ideas -

  • more accepting of interracial

why are we asked to identify ourselves by race?

• census uses for policy making, equal job opportunities, etc

ancestry and race in relation to health

• health disparities

  • e.g. observed racial disparities in kidney disease are large and persistent

    • 12% of black Americans have kidney disease but 35% of population have disease

Dr. Jones’ three levels of racism

1. institutionaized (social structure)

2. personally mediated (between individuals)

3. Internalized (within individuals)

moving forward

• being more aware of population labels in health research

• improve estimation and visualization in genetic research

• include racism as a part of the ‘environment’ in which genetic variation operates