FOP is often referred to as "Stone Man Syndrome" because it causes muscle and tissue to change into bone. Over time, these new bones form a "second skeleton" that greatly inhibits one's mobility.

Causes: FOP is caused by a mutation in a gene called ACVR1, which is involved in a cellular process that regulates the formation of the skeleton in the womb and then orchestrates skeletal repairs ...

Additional bone growth, or heterotopic ossification, is visible around the upper arms and back on a skeleton of a patient with FOP Credit: PR JEAN-DENIS LAREDO, ISM / SCIENCE PHOTO LIBRARY Early ...

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic disorder that turns soft tissue to bone. A recently completed multi-year study will finally provide doctors the information ...