Monday, July 13, 2015

Remember, Race Is A Social Construct

Nothing to do with genetics.  Just ignore articles like this:
San Diego, CA (Scicasts) - Researchers at the University of California, San Diego and the School of Medicine have found that the three-dimensional shape of the cerebral cortex - the wrinkled outer layer of the brain controlling many functions of thinking and sensation - strongly correlates with ancestral background. The study, published online July 9 in Current Biology, opens the door to more precise studies of brain anatomy going forward and could eventually lead to more personalized medicine approaches for diagnosing and treating brain diseases.

"If we can account for a large percentage of brain structure based on an individual's genes, we're in a better position to detect smaller variations in the brain that might be important in understanding disease or developmental issues," said the study's senior author Anders Dale, PhD, professor of radiology, neurosciences, psychiatry and cognitive science, and director of the Center for Translational Imaging and Precision Medicine at UC San Diego.

In their study, the researchers found they could predict with "a relatively high degree of accuracy an individual's genetic ancestry based on the geometry of their cerebral cortex."...

"The geometry of the brain's cortical surface contains rich information about ancestry," said the study's first author, Chun Chieh Fan, MD, a graduate student in cognitive science. "Even in the modern contemporary U.S. population, with its melting pot of different cultures, it was still possible to correlate brain cortex structure to ancestral background."

Four continental populations were used as ancestral references: European, West African, East Asian and Native American. The metrics for summarizing genetic ancestry in each ancestral component were standardized as proportions ranging from 0 to 100 percent.

"We looked to see how well we could predict how much genetic ancestry they had from Africa, Europe and so forth," said study co-author Terry Jernigan, PhD, professor of cognitive science, psychiatry and radiology, adding that cortex differences between various lineages were focused in certain areas. "There were various systematic differences, particularly in the folding and gyrification patterns of the cortex," said Jernigan, also director of the university's Center for Human Development. "Those patterns were quite strongly reflective of genetic ancestry."

The researchers reported that the cortical patterns accounted for 47 to 66 percent of the variation among individuals in their genetic ancestry, depending on the ancestral lineage.


Jim said...

That generic heritage would be noticeable makes perfect sense. "Race" is a social construct, but our genetic heritage can be analyzed and affects our body and mind.

Rich Rostrom said...

"Race" is indeed a social construct. In Kipling's short story "Pig", about a feud between two Anglo-Indian civil servants, he writes that the Yorkshireman "had the race-advantage" over his Devonshire adversary. Alan Paton once wrote of "the great race-divide" of South Africa - meaning between Anglos and Afrikaners.

This does not mean that there are not broad variations in human heredity which are geographically distributed. It's just that humans divide one other into sharp categories which are not actually sharp, and ascribe far more importance to them than they really carry.

Joseph said...

Races do not exist because collectives do not exist. Each human being is a proper class.

Clayton Cramer said...

Every human should be treated as an individual, but collections do exist, and this influences public policy. If you were screening people for Tay-Sachs would it make more sense in Brooklyn or Boise?