Steven Pinker on Personal Genomics
January 12, 2009
My Genome, My Self” in this week’s New York Times magazine.Pinker, who is a 23andMe customer himself and also a participant in George Church’s Personal Genome Project, recommends taking genetic data with a grain of salt. Because as we often point out on The Spittoon, genetics is not fate and the science is still evolving.Pinker, for example, has discovered that he has a genetic variation that increases his chances of going bald. Considering the man’s trademark thick and curly tresses, that one genetic toggle is not the whole story.Pinker recommends personal genomics if you’re curious about how the countless genetic discoveries that are being made almost daily may apply to you personally, and might be relevant to your health down the road. And, we might add, becoming part of the 23andMe community also gives you the opportunity to help advance genetic research into diseases, conditions or traits that interest you. Combined with our community features, which let you find people with whom you share elements of nature AND nurture, personal genomics has great potential to become a tool not just for utilizing scientific advancements but making new ones as well.As Pinker makes it clear however, personal genomics is not about to supplant, or even supplement, preventive medicine any time soon. “If you want to know whether you are at risk for high cholesterol, have your cholesterol measured,” he rightly recommends. (For some other takes on the Pinker piece and the state of personal genomics, check in with our colleagues at Gene Expression and Genetic Future.)One of the most fascinating, albeit technical, parts of the essay is Pinker’s prediction that personal genomics will have more success elucidating the genetic underpinnings of personality than intelligence. Assuming from an evolutionary standpoint that it’s better to be smarter (it also kind of depends on how you define intelligence, but we won’t dwell on that), then over the millennia natural selection has done the work of deleting any genetic variations that substantially decrease intelligence but left intact hundreds or thousands that have negligible influence. Thanks to their tiny effect, those variations will prove very difficult to identify.Evolution appears to foster large personality differences, on the other hand, because different types of people tend to thrive as the environment changes. Consider the recent history of the world’s financial markets — it’s easy to see how both pessimists and optimists could do well, though not necessarily at the same time. And it’s also easy to see how the number of bulls and bears could oscillate as first one side, then the other, got the upper hand. If you’re smart (and lucky) enough, you can make money in the market using either approach.Evolutionary biologists call it balancing selection when two opposing traits are maintained in this way. And geneticists have had considerable success identifying genetic variations that have been subject to balancing selection, just as they have ones that make some people more adventurous, or prone to depression.“It’s still a messy science, with plenty of false alarms, contradictory results and tiny effects. But consumers will probably learn of genes linked to personality before they see any that are reliably connected to intelligence,” Pinker contends.