Behind the Mystery: Fibrodysplasia Ossificans Progressiva (FOP)

FOP, or fibrodysplasia ossificans progressive, is one of the rarest and most disabling genetic conditions known to medicine. It occurs when bone forms in muscles, tendons, ligaments, and other connective tissues.

There are no other known examples in medicine of one normal organ system turning into another. In a sense, people with FOP have an extra skeleton. We meet, Nancy, a courageous patient who has lived with FOP for 60 years. Today, FOP affects every joint in her body, except most of her fingers. At this time, there is no treatment for FOP, and the disorder will only worsen as the body continues to form new bone.

A breakthrough occurred in 2006 when a research team pinpointed a single gene mutation, one letter out of six billion in the human genome that causes the runaway bone growth of FOP. Since the discovery, research efforts for a cure accelerated and spurred drug development to help stop the progression of this disease.