And Now, a Really Big Family Tree

A “genome hacker” has presented what is being called the most comprehensive family tree ever put together.

The tree dates back to the 15th century and accounts for about 13 million people. It was presented by Yaniv Erlich at the annual meeting of the American Society of Human Genetics last month in Boston. Erlich leads a team at the Whitehead Institute for Biomedical Research at the Massachusetts Institute of Technology.

From Nature:

The structures of the trees themselves could provide interesting information about human demographics and population expansions, says Nancy Cox, a human geneticist at the University of Chicago, Illinois, who was not involved in the study. But more interesting, she says, is the possibility that such data may one day be linked to medical information or to DNA sequence data as more people have their genomes sequenced and deposit that information in public databases.

“We’ve really only begun to scratch the surface of what these kinds of pedigrees can tell us,” she says.

Pedigrees provide clues about genetic inheritance. For instance, by comparing an individual to their more distant relatives on the family tree, the change in frequency of a given trait, such as fertility, can indicate to what extent the trait has its roots in genetics. It can also provide clues as to whether the trait is controlled by a few genes that have large effects, or by many genes that each make smaller contributions.

Erlich and his team dug into online genealogy databases to build the tree.

But it takes years to assemble genealogical data for even just a few thousand individuals, said Erlich during a presentation at the meeting on 24 October. In the past, researchers have painstakingly gathered such data from church records and individual volunteers. Erlich and his team decided to streamline the process by collecting data from more than 43 million public profiles on the genealogy website The profiles typically included birth and death dates, as well as locations and, occasionally, photos uploaded by the users.

The team assembled the data into family trees that ranged from a few thousand individuals up to 13 million people in size. Erlich says that pedigrees previously available for genetic studies contained hundreds of thousands of family members at best.

While the research has been made available to other smart folk, the names attached to the data have been scrubbed for privacy purposes. Good thing, too, when you consider the potential devastation awaiting unwittingly incestuous couples.

Read more at Nature.

photo credit: Vox Efx, Creative Commons/flickr