The non-profit MyMicrobes has launched a program that's both a "social network and DNA database," and is inviting people to get their gut bacteria sequenced for about $2,100, reports Nature News' Nicola Jones. The MyMicrobes Web site, started by a team of microbial researchers in Europe, offers a place for people to share diet tips, advice on gastrointestinal problems, and more, Jones says, adding that the researchers hope to gather as much data about gut microbes and how they affect people as possible. "So far, the team has found links between certain gut-specific genetic markers and obesity and other diseases. And they suspect that gut enterotypes might affect how people react to different drugs and diets," Jones says. After registering on the site, users are shipped packages containing information on the project and a stool sample kit — the kits are mailed to a lab in Paris where the DNA is extracted and sent to Heidelberg for sequencing. So far, the researchers say they have about 100 interested participants, but estimate they'll need around 5,000 to power significant study results, Jones reports.