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Children's Health

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Chromosome 22, Trisomy Mosaic

It is possible that the main title of the report Chromosome 22, Trisomy Mosaic 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.


Disorder Subdivisions

  • None

General Discussion

Chromosome 22, Trisomy Mosaic is a rare chromosomal disorder in which chromosome 22 appears three times (trisomy) rather than twice in some cells of the body. The term "mosaic" indicates that some cells contain the extra chromosome 22, whereas others have the normal chromosomal pair.

The range and severity of associated symptoms and findings may vary, depending upon the percentage of cells with the chromosomal abnormality. However, characteristic features typically include growth delays, mental retardation, unequal development of the two sides of the body (hemidystrophy), and webbing of the neck. Affected individuals may also have abnormal outward deviation of the elbows upon extension (cubitus valgus), multiple pigmented moles or birthmarks (nevi), distinctive malformations of the head and facial (craniofacial) area, and other physical abnormalities.


Support Organization for Trisomy 18, 13, and Related Disorders
2982 S. Union Street
Rochester, NY 14624-1926
Fax: (585)594-1957
Tel: (800)716-7638

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

The Arc
1825 K Street NW, Suite 1200
Washington, DC 20006
Tel: (202)534-3700
Fax: (202)534-3731
Tel: (800)433-5255
TDD: (817)277-0553

American Heart Association
7272 Greenville Avenue
Dallas, TX 75231
Tel: (214)784-7212
Fax: (214)784-1307
Tel: (800)242-8721

Support Organization for Trisomy 13/18 and Related Disorders, UK
c/o Christine Rose
48 Froggatts Ride
Sutton Coldfield
West Midlands, B76 2TQ SOFT
United Kingdom
Tel: 01213513122

UNIQUE - Rare Chromosome Disorder Support Group
P.O. Box 2189
Surrey, CR3 5GN
United Kingdom
Tel: 4401883330766
Fax: 4401883330766

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: 5/31/2008
Copyright 1994, 2000, 2003 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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