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Children's Health

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Jansen Type Metaphyseal Chondrodysplasia

It is possible that the main title of the report Jansen Type Metaphyseal Chondrodysplasia 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.


  • Jansen disease
  • Jansen metaphyseal dysostosis
  • Murk Jansen type metaphyseal chondrodysplasia

Disorder Subdivisions

  • None

General Discussion

Jansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbous) end portions (metaphyses) of these long bones (metaphyseal chondrodysplasia). As a result, affected individuals exhibit unusually short arms and legs and short stature (short-limbed dwarfism), findings that typically become apparent during early childhood. Abnormal cartilage and bone development may also affect other bones of the body, particularly those of the hands and feet (i.e., metacarpals and metatarsals). Infants with Jansen type metaphyseal chondrodysplasia may also have characteristic facial abnormalities and additional skeletal malformations. During childhood, affected individuals may begin to exhibit progressive stiffening and swelling of many joints and/or an unusual "waddling gait" and squatting stance. In addition, affected adults may eventually develop abnormally hardened (sclerotic) bones especially in the back of the head (cranial bones), which, in some cases, may lead to blindness and/or deafness. In addition, affected individuals have abnormally high levels of calcium in the blood (hypercalcemia). The range and severity of symptoms may vary from case to case. Most cases of Jansen type metaphyseal chondrodysplasia occur randomly as the result of a spontaneous genetic change (i.e., new genetic mutation).


Human Growth Foundation
997 Glen Cove Avenue
Suite 5
Glen Head, NY 11545
Tel: (516)671-4041
Fax: (516)671-4055
Tel: (800)451-6434

MAGIC Foundation
6645 W. North Avenue
Oak Park, IL 60302
Tel: (708)383-0808
Fax: (708)383-0899
Tel: (800)362-4423

Little People of America, Inc.
250 El Camino Real Suite 201
Tustin, CA 92780
Tel: (714)368-3689
Fax: (714)368-3367
Tel: (888)572-2001

NIH/National 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

NIH/National Institute on Deafness and Other Communication Disorders
31 Center Drive, MSC 2320
Communication Avenue
Bethesda, MD 20892-3456
Tel: (301)402-0900
Fax: (301)907-8830
Tel: (800)241-1044
TDD: (800)241-1105

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

Craniofacial Foundation of America
975 East Third Street
Chattanooga, TN 37403
Tel: (423)778-9176
Fax: (423)778-8172
Tel: (800)418-3223

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

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 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 or email

Last Updated: 5/8/2012
Copyright 1997, 1998, 2004, 2005, 2008, 2012 National Organization for Rare Disorders, Inc.

WebMD Medical Reference from the National Organization for Rare Disorders

Last Updated: May 28, 2015
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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