Suggestive though they are, these findings so far lack the real-world application that can turn even the most questionable longevity fads, like Resveratrol, into worldwide sensations. After all, as Tommy Kahn puts it, would you really want to know if you have a predisposition for your penis falling off unless there were “some kind of splint” you could get to repair it? (Tommy, a widower, recently remarried.)
But the Einstein project is fascinating for a major reason beyond its science: Its main test group consists entirely of Ashkenazim—that is, Jews who descend, as more than 80 percent of American Jews do, from communities in the Pale of Settlement of Eastern Europe. In longevity news, the spotlight frequently passes from one group to another: Georgian yogurt eaters, Japanese pensioners, the Pennsylvania Dutch. But 540 Jews in a New York–based study of extreme old age is too delicious. The mind cramps with the possibility of jokes.
Barzilai acknowledges as much, telling me first off that most of the original intakes were done by a Gentile nurse named William Greiner. After Greiner visited the participants in their homes, interviewing them and taking their blood, Barzilai would get calls saying that the young man was very nice, but why didn’t he touch the cake they’d prepared?
Mostly gray at 56, Barzilai, Israeli by birth, is a puffball of excitability: twinkling, gesturing, capable of persuading anyone to do anything. Well, almost anyone. His mother, a Holocaust survivor born in what is now Ukraine, refused to let him test her blood. “For her, the genetic studies had already been done,” Barzilai recalls. “And she didn’t enjoy it the first time.”
He laughs, but the twinning of darkness and lightness in his life’s work is no accident. Longevity is the flip side of mortality, as Jews who survived the twentieth century do not need reminding. When a centenarian says she’s Ashkenazic, he takes her word for it: “Do you think there would be impostors?” And when he goes to synagogues to solicit volunteers, he makes this argument: “Yes, we had a miserable history, okay, let’s get over that, we ended up not in such a bad place. And if we’re able to give back, to find genes associated with longevity, it’s really something we have to do. I’m not choosing Ashkenazim because of only a technical point, but also tikkun olam”—the rabbinic injunction to repair the world.
As it turns out, the miserable history is inseparable from the technical point. Barzilai centered his studies on Ashkenazim not because they live longer or produce more centenarians than other ethnic groups. They don’t. It’s that their unusual development as a homogeneous community makes them easier to study at the level of DNA. Genetic research done by Barzilai’s Einstein colleague Gil Atzmon suggests that Ashkenazim branched off from other Jews around the time of the destruction of the First Temple, 2,500 years ago. They flourished during the Roman Empire but then went through a “severe bottleneck” as they dispersed, reducing a population of several million to just 400 families who left Northern Italy around the year 1000 for Central and eventually Eastern Europe. Though their numbers increased dramatically once there, to some 18 million before the Holocaust, studies suggest that 40 percent of today’s Ashkenazim descend from just four Jewish mothers. How proud those mothers would be to know that the reason their mishpocheh has remained far more genetically alike than a random population—Barzilai says by a factor of at least 30—is that until recently their sons almost never married outside the clan.
That likeness means that small genetic differences—as small as one “letter” of DNA code—are more easily spotted on Ashkenazi genes than on those of, say, Presbyterians. Icelanders are good, too: They are all descendants, Barzilai says, of five Viking men and four Irish women. But they are a tiny population, with proportionately fewer centenarians, and aren’t so easy to find in New York. Ashkenazim are plentiful. And because they are also fairly similar in their educational and economic status, some of the variables that can muddy the picture are already controlled.
Others are controlled more explicitly. An Einstein study published in August asked whether the SuperAgers, over the course of their lives, had better health habits than the general population.
The answer was no; their habits were, if anything, worse. They smoked as much or more than others and were no better about diet or exercise. Tommy Kahn described his father’s lifelong eating habits as “lamb chops one night, steak the next.” Exercise was sporadic and mild. “Healthy living can get you past 80,” says Barzilai, “but not to 100.” Something else is at play. When asked what they themselves thought it might be, the participants offered such explanations as genes, luck, and family history. God, says Barzilai, finished last.