Genetics of race

From RationalWiki
Jump to: navigation, search

If race were more than just a social construct, the genetics of race should show differences strongly associated with the definitions of race. Historically race has been described as overlapping with ethnicity and whatever is convenient to differentiate between us and the various categories of them. The easiest distinctions come from things like skin color, hair, and eye shape which, yes, are genetically based, but the surface commonality is not enough to justify racial stereotypes. For those stereotypes to be true, the genetics of race have to extend deeper. Research does show that, with enough genetic information (i.e. more than 1000 genetic loci), it is possible to quite accurately identify the geographic origin of a sampled person, but only when the chosen regions are quite distinct.[1] Even then, Witherspoon concludes:

The fact that, given enough genetic data, individuals can be correctly assigned to their populations of origin is compatible with the observation that most human genetic variation is found within populations, not between them. It is also compatible with our finding that, even when the most distinct populations are considered and hundreds of loci are used, individuals are frequently more similar to members of other populations than to members of their own population. Thus, caution should be used when using geographic or genetic ancestry to make inferences about individual phenotypes.[1]


Contents

[edit] Genes

There are several ways genes themselves can determine, in part, any differences that may be attributable to race. The genotype itself can differ where genetic codes systematically differ from race to race. Even with identical genes across races, the expression of the genes can differ.

[edit] Genotype

Genetic data does show that random people sampled from within a population are generally more similar to each other than a pair sample from different populations.[1] That's hardly surprising since, when left to their own devices, people tend to procreate with local folk more than with folk from another part of the world (a notable exception: wife-importing MGTOW). It's just easier that way. Sometimes cousins even hook up with cousins. Certain traits tend to cluster in certain areas. The highest level of long distance runners comes not just from Kenya, but a particular part of Kenya and their success is defined, in part, by common genetics.[2] But that isn't race. In fact, the opposite end of the running spectrum, sprinters, features a large proportion with origins in Eastern Africa.[3] Both sets of genes favor running, but entirely different aspects of it. By these genes alone, the two groups might appear to be different races, even while our knee-jerk appearance-based definitions put them in the same race.

[edit] Epigenetics

Along the way from chemistry to expression, the environment gets its chance to intervene. Epigenetics studies the way in which factors outside of the DNA itself alter the way in which genes are expressed. Resembling Lamarckian genetics, epigenetic effects can be remarkable enough for a mouse to pass a specific fear response down at least two generations (F3).[4] In humans, increased risk for cardiovascular disease among African Americans is hypothesized to result genetic expression modified by in utero experience of maternal stressors. [5] Epigenetic effects might tie socioeconomics to future IQ, explaining some portion of controversially observed racial differences. [6][7]

[edit] Phenotype

Expressed genes turn into phenotypes, the actual manifestation of differences. Phenotype is, at times, fairly close to genotype and, thus, might fit into the genetics of race.

Applying the same technique as Witherspoon [1], Strauss and Hubbe analyzed data of head shape and found that, across three regions that correspond to three common racial definitions, a typical person in any region was about 30% likely to be more similar to someone from a different region than to someone within their own region.[8] In other words, head shape, one defining factor of race, does not correspond consistently to geographical heritage in the way it would be expected were genetic differences determinant of race. In even shorter words, the genotype may be similar among a race, but phenotype is less similar. This may explain how one white supremacist was so surprised to discover his African heritage.[9]

[edit] Alternate views

Why stop with simplistic appearance-based racial definitions? Why not consider other definitions for which there are genetic determinants?

  • Type B blood: Native Americans (First Nations for residents of Canuckistan) and Aboriginal Australians would form one race while Africans would be form up partly with Europeans and partly with Asians.[10]
  • Sickle-cell anemia risk: One race would encompass the major malaria risk zones of Central and Northern Africa, parts of the Mediterranean, Arabia, and India.[11]
  • The ability to digest milk sugar in adulthood[wp]: much more common in areas where dairy farming has been practised for thousands of years.[12]
  • Defined by one gene alone, you could divide the world into sprinters (strong RR on ACTN3), long-distance runners (strong RX on ACTN3), and everyone else. [3] Geographically, that's people with West African heritage, East African Heritage, and everyone else.

[edit] See also

[edit] Footnotes

Personal tools
Namespaces

Variants
Actions
Navigation
Community
Tools
support