Some people harbor a gene variant that accounts for accelerated aging of their brains after the age of 65, the International Business Times reports. It adds that this variant may influence people's risk of neurodegenerative disease.
A pair of researchers at Columbia University examined the transcriptomes of 1,904 autopsied human brain samples to get a sense of what the average brain is like at various ages. They then compared the brains in their sample to that average to determine whether they appeared older or younger than their actual age. In a subsequent genome-wide association study, the researchers linked the TMEM106B gene to differential aging in the brain. As they report today in Cell Systems, the researchers note that the role of TMEM106B in aging appears to be age- and central nervous system region-specific.
Before the age of 65, "everybody's in the same boat, and then there's some yet-to-be-defined stress that kicks in," co-author Asa Abeliovich tells Agence France-Presse. "If you have two good copies of the gene, you respond well to that stress. If you have two bad copies, your brain ages quickly."
He adds that people who have two copies of the variant could have a brain that appears a dozen years older than those without that variant.