The shape of the follicle is also necessary just for keeping the hairs growing in the same direction. Hamilton’s colleague Alexey Terskikh learned this a few years ago, when his lab cloned human hair follicles and transplanted them into mice—only for many of the hairs to grow inward or sideways. Those that did sprout through the skin came out at all different angles. “Simply putting the follicle in the skin means a lot of ingrown hairs and lots of weird directions,” says Hamilton. Even slight differences in angle make hair look deeply unnatural.

This discovery has launched a global arms race to generate sustainable hair follicles that will hold their shape. At the meeting last month, Hamilton’s group proposed one solution. It involves a synthetic scaffold, which Hamilton will describe only as proprietary. The scaffold would be implanted around the cloned follicle to direct the growth of the hair. Stemson Therapeutics recently partnered with the pharmaceutical giant Allergan to develop this scaffold for cloned hair, and Hamilton says they expect to start a clinical trial in humans in about a year and a half.