Fibrodysplasia ossificans progressiva is a rare connective-tissue
disorder characterized by congenital malformation of the great toes and by
progressive heterotopic ossification of the tendons, ligaments, fasciae,
and skeletal muscles. We document the genetic transmission of
fibrodysplasia ossificans progressiva from a sporadically affected father
to each of his three children: two daughters and a son. Previous
consideration of a genetic etiology was based on the fact that the disease
has been reported in several sets of monozygotic twins, that an increased
paternal age has been associated with sporadic occurrences of the disorder,
and that there have been several reports of genetic transmission in the
remote past. Although an autosomal-dominant genetic transmission has long
been suspected, the findings in the family reported on here provide
confirmation for such inheritance and a basis for the diagnosis and
counseling of patients who have this disease.