Mice, Men, and Fate

The New Yorker:

Almost fifteen years ago, in a book called “Chance, Development, and Aging,” the gerontologists Caleb Finch and Thomas Kirkwood described a truly elegant study of biology: a batch of roundworms, all genetically identical, raised on identical diets of agar. Despite having identical genetics and near-identical environments, some worms lived far longer than others. The lesson? The classical equation of “life = nature + nurture” had left out chance.

Of course, that was just worms. This week, a team of German researchers, led by Gerd Kempermann, built on a similar logic and announced in Science that they had raised forty inbred mice that were essentially genetically identical in a single complex environment, and used radio-frequency identification (RFID) implants to track every moment of their lives. Nobody could ever ethically run that sort of controlled experiment with humans, but Kempermann’s study provides convincing evidence that—in a fellow mammal with which we share a basic brain organization—neither genetic identity nor a shared environment is enough to guarantee a common fate. Different creatures, even from the same species, can grow up differently, and develop significantly different brains—even if their genomes are identical, and even if their environments are, too.

Read the whole story: The New Yorker