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Hereditary Multiple Osteochondromas

National Organization for Rare Disorders, Inc.

Important
It is possible that the main title of the report Hereditary Multiple Osteochondromas 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.

Synonyms

  • EXT
  • hereditary multiple exostoses
  • multiple osteochondromas
  • diaphyseal aclasis
  • external chondromatosis syndrome
  • multiple cartilaginous exostoses
  • multiple exostoses
  • multiple exostoses syndrome
  • multiple osteochondromatosis

Disorder Subdivisions

  • None

General Discussion

Summary
Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, arms, and digits. These osteochondromas usually continue to grow until shortly after puberty and may lead to bone deformities, skeletal abnormalities, short stature, nerve compression and reduced range of motion. Hereditary multiple osteochondromas is inherited as an autosomal dominant genetic condition and is associated with abnormalities (mutations) in the EXT1or EXT2 gene.

Introduction
Hereditary multiple osteochondromas was formerly called hereditary multiple exostoses.

Resources

NIH/National Institute of Arthritis and Musculoskeletal and Skin Diseases
Information Clearinghouse
One AMS Circle
Bethesda, MD 20892-3675
USA
Tel: (301)495-4484
Fax: (301)718-6366
Tel: (877)226-4267
TDD: (301)565-2966
Email: NIAMSinfo@mail.nih.gov
Internet: http://www.niams.nih.gov/

MHE Coalition
6783 York Road, Apt. #104
Parma Heights, OH 44130-4596
USA
Tel: (440)842-8817
Email: CheleZ1@yahoo.com
Internet: http://www.mhecoalition.org

MHE and Me- A Support Group for Kids with Multiple Hereditary Exostoses
PO Box 651
Pine Island, NY 10969-0651
USA
Tel: (845)258-6058
Fax: (845)258-6058
Email: mheandme@yahoo.com
Internet: http://www.mheandme.com/

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
Internet: http://rarediseases.info.nih.gov/GARD/

MHE Research Foundation
79-77 Street
Brooklyn, NY 11209
Tel: (718)569-0479
Fax: (201)786-1758
Tel: (877)486-1758
Email: sarahziegler@mheresearchfoundation.org
Internet: http://mheresearchfoundation.org

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to www.rarediseases.org and click on Rare Disease Database under "Rare Disease Information".

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 www.rarediseases.org or email orphan@rarediseases.org

Last Updated:  9/19/2012
Copyright  1993, 2000, 2008, 2012 National Organization for Rare Disorders, Inc.

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