Genes Important to Keep Brain Sharp Through Old Age

Live Science ^ | 18 January 2012 | Jennifer Welsh

[Pharmboy]

A person's intelligence is mostly inherited, it's in their genes, but whether a person can expect to be a clever grandma or grandpa relies on both genes and environment.

"Until now, we have not had an estimate of how much genetic differences affect how people's intelligence changes across the lifetime," study researcher Ian Deary, of the University of Edinburgh in the United Kingdom, said in an email to LiveScience. "These new results mean that researchers can seek both environmental and genetic contributionsto successful cognitive aging."

Previous studies of the genetics of intelligence have been performed on sets of twins or siblings who have been adopted and raised in different environments. These studies showed a genetic component of intelligence, but previous studies weren't able to determine how this changes over a lifetime.

Smart Scots

The researchers studied a group of 1,940 Scottish individuals whose intelligence was measured when they were 11 years old. They were tracked down recently and had their intelligence measured again in old age (65, 70 or 79 years of age). The researchers also collected genomic data from blood samples.

[Pharmboy]

It's one-quarter of your genes rather than your 46 chromosomes that you inherit from grandparents...doesn't that make it easier? And the chromosomes trade parts with each other and are not immutable...

[aculeus]

Stephen Jay Gould, call your office.

Exactly. The damage he and Lewontin inflicted on American biology will take decades to fix.