James Watson, co-discoverer of the double helix, gave the Alumni Convocation address at the University of Chicago last weekend. His genome had been sequenced, he said, but he didn’t want to know if he had “the Alzheimer’s gene”. This is misleading. It implies too much certainty, like a measurement with too many digits. It is entirely possible that this “Alzheimer’s gene” determines one’s vulnerability to low levels of omega-3s and that with sufficient omega-3 it makes no difference. My flaxseed-oil research suggests that almost everyone is omega-3 deficient (because the optimum amount of flaxseed oil was so high). A study of persons 65 or older found that more fish consumption was associated with less cognitive decline.
Am I saying there is gene-environment interaction? Well, is there a “scurvy gene”? Surely there are genes that affect one’s sensitivity to low levels of Vitamin C. But no one cares about them — because most people get enough Vitamin C to avoid scurvy.