Sarah Zhang: You’ve constructed a family tree connecting 13 million people. That’s quite an accomplishment, and so rather than let you bask in it, let me ask: Would it be possible to construct a family tree that connects every single living person in the world?

Yaniv Erlich: There is a theory you need to go 75 generations or so to connect everyone in the world. By everyone, I mean everyone. I’m talking about people in some tribes in the Amazon to someone in Iceland. So it’s possible, but there are no really good ways to trace so deeply. Maybe with genetics we can start to bridge gaps where the genealogy is not there.

Zhang: How did you get interested in genealogy?

Erlich: It’s a bit of a long story. Every kid in Israel in seventh grade needs to do a genealogy project. I did my genealogy and I was so excited about it. In fact, I won the school award for the best project.

Now at the end of 2008, my third cousin that is really into genealogy told me about this website Geni.com. He emailed me like, “Oh, do you want to put in some people in your family?” I was looking at the data and I was thinking—this was toward the end of my Ph.D.—somebody should download the data and do something cool about it. I didn’t have any application in mind.

Then in 2010, I started my own lab at the Whitehead Institute [at MIT]. I was sitting there thinking what I can do and reading a bit about how to mine social media. There was a book, Mining the Social Web. I sent a cold email to the CTO of Geni, asking if I could download the data. It’s a cold email, who knows right? He got back to me saying, “Yeah, you can download the data, no problem,” and gave me some pointers on how to do that.

Zhang: Your study is published now, but it seems like this is a beginning rather than an end. I’d imagine what you’re really interested in is overlaying genetic data on top of the family tree.

Erlich: Exactly. At MyHeritage, we started to offer DNA tests to users in November 2016. Since then we’ve collected 1.2 million DNA profiles of users.

Zhang: And why make the jump to MyHeritage? Are there things you can do at a company you couldn’t do in academia?

Erlich: I think this is a model for the future. There are certain things that you can only do in academia. There are certain things you can only do in companies. If you want to move in scientific endeavors, collaborating with companies is a very fruitful direction.

I could not do this study if I was just in a company because it’s years and years of process, and this is academic freedom that I could actually take this time. On the other hand, if there are no companies, nobody would collect this data. This amount of data, you cannot get it in academic studies. Companies have the ability to reach out to millions of genealogists, to work with them, to convince them to give the data, to give them the good feeling about it. You need a company that has websites that are perfect, that are responsive, that are fun to use. Not PubMed, which is a nice website but has a very geeky look.