A new study looks at the roles that African and European genetic ancestries can play in Black Americans' risk for some brain disorders. TEK IMAGE/SCIENCE PHOTO LIBRARY/Getty Images hide caption Black Americans are known to be at higher risk of some neurological disorders, and the reasons for this disparity remain unclear. Now, after examining the postmortem brains of 151 people, researchers in Baltimore have identified genes that may help explain why.
In those people, who all identified as Black or African American, the scientists analyzed the influence of two different ancestries: African and European. They found that genes associated with African ancestry appear to affect certain brain cells in ways that could increase the risk of Alzheimer’s disease and stroke. But genes associated with European ancestry seem to influence other brain cells in ways that could increase the risk of Parkinson’s disease, a disorder that is less common in Black Americans.
The study also probed whether genetic ancestry influenced neurons, which are critical to memory, movement, and thinking. Neurons appear to play an important role in certain psychiatric disorders, including schizophrenia, which are diagnosed more frequently in Black Americans than their white counterparts. Yet the researchers found no evidence that genetic ancestry influenced neurons.
This could mean that societal factors, such as economic and psychological stress, exposure to traumatic events, and racial bias in diagnosis, .
