About FOP
Fibrodysplasia ossificans progressiva (FOP) is a genetic disorder in which muscle tissue and connective tissue such as tendons and ligaments are gradually replaced by bone (ossified), forming bone outside the skeleton (extra-skeletal or heterotopic bone) that constrains movement. This process generally becomes noticeable in early childhood, starting with the neck and shoulders and proceeding down the body and into the limbs.
Extra-skeletal bone formation causes progressive loss of mobility as the joints become affected. Any trauma to the muscles of an individual with fibrodysplasia ossificans progressiva, such as a fall or invasive medical procedures, may trigger episodes of muscle swelling and inflammation (myositis) followed by more rapid ossification in the injured area. Flare-ups may also be caused by viral illnesses such as influenza.
People with fibrodysplasia ossificans progressiva are generally born with malformed big toes. This abnormality of the big toes is a characteristic feature that helps to distinguish this disorder from other bone and muscle problems. Affected individuals may also have short thumbs and other skeletal abnormalities.
There are only 800 known cases worldwide and 185 in the US. On April 23, 2006, it was discovered that only a single amino acid substitution causes FOP. In FOP, the ACVR1 gene is damaged by the substitution of a single genetic letter at a specific location in the gene. The single nucleotide substitution changes the meaning of the genetic message encoded by the ACVR1 gene. “Thus, the substitution of one genetic letter for another out of six billion genetic letters in the human genome – the smallest and most precise change imaginable – is like a molecular terrorist that short circuits a functioning set of muscles and connective tissues and transforms them into a second skeleton – in essence turning a light bulb into an atom bomb,” - Dr. Kaplan.
Now, researchers are developing clinical trials that will hopefully start very soon. For more information, or to donate, please visit www.ifopa.org.
Extra-skeletal bone formation causes progressive loss of mobility as the joints become affected. Any trauma to the muscles of an individual with fibrodysplasia ossificans progressiva, such as a fall or invasive medical procedures, may trigger episodes of muscle swelling and inflammation (myositis) followed by more rapid ossification in the injured area. Flare-ups may also be caused by viral illnesses such as influenza.
People with fibrodysplasia ossificans progressiva are generally born with malformed big toes. This abnormality of the big toes is a characteristic feature that helps to distinguish this disorder from other bone and muscle problems. Affected individuals may also have short thumbs and other skeletal abnormalities.
There are only 800 known cases worldwide and 185 in the US. On April 23, 2006, it was discovered that only a single amino acid substitution causes FOP. In FOP, the ACVR1 gene is damaged by the substitution of a single genetic letter at a specific location in the gene. The single nucleotide substitution changes the meaning of the genetic message encoded by the ACVR1 gene. “Thus, the substitution of one genetic letter for another out of six billion genetic letters in the human genome – the smallest and most precise change imaginable – is like a molecular terrorist that short circuits a functioning set of muscles and connective tissues and transforms them into a second skeleton – in essence turning a light bulb into an atom bomb,” - Dr. Kaplan.
Now, researchers are developing clinical trials that will hopefully start very soon. For more information, or to donate, please visit www.ifopa.org.
Dr. Kaplan
On 12-12-12, Daniel and I met with Dr. Fred Kaplan, THE FOP doctor based in Philadelphia. I can't say enough about this wonderful man and his team at the University of Pennsylvania School of Medicine. They are working tirelessly to find treatment and cures for FOP. Read our diagnosis story here.