by Linda A. Johnson

In this Feb. 12, 2019 photo, Meghan Waldron walks down the street in Boston. Waldron is a student at Emerson College with progeria, one of the world’s rarest diseases. The first treatment has been approved for progeria, Friday, Nov. 20, 2020. The U.S. Food and Drug Administration on Friday approved Zokinvy which was shown in testing to extend patients’ lives by 2 ½ years on average. (Suzanne Kreiter/The Boston Globe via AP)

The first drug was approved Friday for a rare genetic disorder that stunts growth and causes rapid aging in children, after studies showed it