Williams syndrome is the genetic condition that makes people pathologically friendly — in a lonely world

Since he was 5, Tobi Akbas has been nicknamed "the Mayor" in the affluent suburb of Garrison, New York, where he lives. When his mom would take him to the supermarket, he would say hi to every person they saw. In high school, he'd wait in front of the school building to greet students as they arrived.

Now 22, Tobi still craves human connection like oxygen. He's the unofficial ambassador of a Garrison volunteer firefighting squad, handing out candy canes at the annual Santa Run. He posts motivational "Tobi tips" online — as well as sharing them with anyone who asks.