The gene is part of a specific signaling pathway that scientists had found could turn on and turn off hair growth in mice, but a connection to human hair growth had not been made. The gene is disrupted in certain families with hereditary hypotrichosis simplex, Christiano said, showing that the pathway plays a key role in controlling human hair growth, as well as mice.

Why didn't my financial adviser tell me about this before suggesting I invest in the mouse toupee and electrolysis company.