It Takes a Genome: How a Clash Between Our Genes and Modern Life Is Making Us Sick

Slow Walk to Dementia

Surely the most aggravating sign of the teasing and fickle nature of our genes is their insistence on gradual decay. And there is no more certain sign of their power than the decline of Ronald Reagan. Within a decade of leaving the Oval Office of the White House, the man who helped bring the Soviet Union to its knees was himself reduced to a mental crawl by a handful of errant nucleotides sitting around in his genome.

Many would say they saw the signs of Alzheimer’s disease well before he even left the Presidency. But who can say whether his inability to remember the press corps’ questions was an early sign of dementia, or the polished acting performance of a master politician? What we do know is that the course of the ...