Go ahead, marry your cousin—it's not that bad for your future kids
Yaniv Erlich has a soft spot for genealogy. A data scientist at Columbia University and the chief science of officer of the DNA test company MyHeritage, he describes many things in the context of family. Columbia and MyHeritage are “mom and dad” and he’s “got to make both happy.” And his new study on a 13 million-member family tree is best measured in terms of his child’s development. “My son was born when I started the study,” Ehrlich says of the seven year project. “Now, he is in first grade.” The paper, published Thursday in the journal Science, looks at genetic data from millions of online genealogy profiles. Among other things, the researchers were able to determine at what point in history marrying your cousin went out of vogue, and the average degree of relation between married couples today. And hey, since we’re on the subject: just how bad is it to have kids with your cousin? While it’s taboo today, cousins used to get hitched all the time. Franklin Delano Roose...