<unk>  is caused by an autosomal dominant allele on chromosome 2q23-24. The allele has variable expressivity, but complete penetrance. Most cases are caused by spontaneous mutation in the gametes; most people with<unk>  cannot or choose not to have children. A similar but less catastrophic disease is fibrous dysplasia, which is caused by a post-zygotic mutation. A mutation in the gene ACVR1 (also known as activin-like kinase 2 (ALK2)) is responsible for the disease. ACVR1 encodes activin receptor type-1, a BMP type-1 receptor. The mutation causes substitution of codon 206 from arginine to histidine in the ACVR1 protein. This substitution causes abnormal activation of ACVR1, leading to the transformation of connective tissue and muscle tissue into a secondary skeleton. This causes endothelial cells to transform to mesenchymal stem cells and then to bone.
Fibrodysplasia ossificans progressiva
Fibrous dysplasia of bone
Myositis ossificans
Langer–Giedion syndrome
Gerodermia osteodysplastica
Osteitis fibrosa cystica
Enchondromatosis
Osteoma cutis