Fibrodysplasia Ossificans Progressiva (FOP)

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Fibrodysplasia Ossificans Progressiva (FOP)

National Organization for Rare Disorders, Inc.

It is possible that the main title of the report Fibrodysplasia Ossificans Progressiva (FOP) is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • FOP
  • Myositis Ossificans Progressiva

Disorder Subdivisions

  • None

General Discussion

Fibrodysplasia ossificans progressiva (FOP) is a very rare inherited connective tissue disorder characterized by the abnormal development of bone in areas of the body where bone is not normally present (heterotopic ossification), such as the ligaments, tendons, and muscles. Specifically, this disorder causes the body's skeletal muscles and soft connective tissue to undergo a metamorphosis, essentially a transformation into bone, progressively locking joints in place and making movement difficult or impossible. FOP is characterized by malformation of the big toe that is present at birth (congenital). As the disease progresses, there may be other skeletal malformations and the abnormal development of bone may lead to stiffness in affected areas and limited movement in affected joints (e.g.,knees, wrists, shoulders, spine, and/or neck).

Fibrodysplasia ossificans progressiva usually begins during early childhood and progresses throughout life. Most cases of FOP occur as the result of a sporadic new mutation. The genetic mutation that results in this disorder has been identified. FOP is caused by the mutation of a gene in the "BMP pathway", which is associated with the formation of the skeleton in the embryo and the repair of the skeleton following birth.


International Fibrodysplasia Ossificans Progressiva Association
P.O. Box 196217
Winter Springs, FL 32719-6217
Tel: (407)365-4194
Fax: (407)365-3213

March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
Tel: (914)997-4488
Fax: (914)997-4763
Tel: (888)663-4637

NIH/NationaI Institute of Arthritis and Musculoskeletal and Skin Diseases
Information Clearinghouse
One AMS Circle
Bethesda, MD 20892-3675
Tel: (301)495-4484
Fax: (301)718-6366
Tel: (877)226-4267
TDD: (301)565-2966

Coalition for Heritable Disorders of Connective Tissue
4301 Connecticut Avenue, NW, Suite 404
Washington, DC 20008
Tel: (202)362-9599
Fax: (202)966-8553
Tel: (800)778-7171

MUMS National Parent-to-Parent Network
150 Custer Court
Green Bay, WI 54301-1243
Tel: (920)336-5333
Fax: (920)339-0995
Tel: (877)336-5333

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223

UCSF Fibrodysplasia Ossificans Progressiva Clinic
533 Parnassus Avenue
UC Hall U-504
Box 0734
San Francisco, CA 94143
Tel: (415)476-7242
Fax: (415)476-9976
Tel: (888)689-8273

Fundación FOP
Bonpland 1964- Dto 3 PA (1414) Ciudad Autónoma
Buenos Aires,
Tel: 54-911-15-4145-5391
Fax: 54-11-4771-7927

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc. ® (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated:  11/17/2008
Copyright  1987, 1990, 1996, 2002, 2006, 2008 National Organization for Rare Disorders, Inc.

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