Fragile X Syndrome
Important
It is possible that the main title of the report Fragile X Syndrome
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
- Fragile Site, Folic Acid Type, Rare, Fra(X)(Q27.3)
- Marker X Syndrome
- Martin-Bell Syndrome
- X-linked Mental Retardation and Macroorchidism
- Fragile X Mental Retardation Protein, FMRP
- Fragile X Mental Retardation Syndrome
- Mental Retardation, X-Linked, Associated With Mar Xq28
Disorder Subdivisions
- None
General Discussion
Fragile X syndrome is characterized by moderate mental retardation in affected males and mild mental retardation in affected females. Distinctive physical features are sometimes present in affected males including a large head, long face, prominent forehead and chin, protruding ears, loose joints and large testes, but these features develop over time and may not be obvious until puberty. Motor and language delays are usually present but also become more apparent over time. Behavioral abnormalities including autistic behaviors are common.
Fragile X syndrome is caused by an abnormality (mutation) in the FMR1 gene. Affected individuals have an increased number of copies of a portion of the gene called CGG repeats. The greater the number of copies of CGG, the more likely the increased severity of the disorder. Fragile X syndrome occurs more often in males and results in more severe disease in males.
Mutations in the FMR1 gene are associated with two other conditions in addition to the fragile X syndrome (FXTAS and POF) and these conditions have been termed FMR1-Related Disorders. (See the Related Disorders section of this report for brief summaries of the other disorders.)
Resources
The Arc (a national organization on mental retardation)
1010 Wayne Ave
Suite 650
Silver Spring, MD 20910
Tel: (301)565-3842
Fax: (301)565-3843
Tel: (800)433-5255
TDD: (817)277-0553
Email: info@thearc.org
Internet: http://www.thearc.org/
FRAXA Research Foundation
45 Pleasant Street
Newburyport, MA 01950
USA
Tel: 9784621866
Fax: 9784639985
Email: info@fraxa.org
Internet: http://www.fraxa.org
National Fragile X Foundation
PO Box 190488
San Francisco, CA 94119
USA
Tel: 9259389300
Fax: 9259389315
Tel: 8006888765
Email: NATLFX@FragileX.org
Internet: http://www.FragileX.org
New York State Institute for Basic Research in Developmental Disabilities
1050 Forest Hill Road
Staten Island, NY 10314
Tel: (718)494-0600
Fax: (718)698-3803
TDD: (718)494-5117
Email: vietcoat@ix.netcom.com
NIH/National Institute on Aging
PO Box 8057
Gaithersburg, MD 20892-8057
Tel: (301)496-1752
Tel: (800)222-2225
Internet: http://www.nih.gov/nia
Simon, Valerie, M.D.
Kennedy-Krieger Institute
Behavioral Genetics Unit
Room 103
707 North Broadway Avenue
Baltimore, MD 21205
Tel: (301)550-9321
NIH/National Institute of Child Health and Human Development
31 Center Dr
Building 31, Room 2A32
MSC2425
Bethesda, MD 20892
Tel: (301)496-5133
Fax: (301)496-7101
Internet: http://www.nih.gov/hichd/
New Horizons Un-Limited, Inc.
811 East Wisconsin Ave
Suite 937
Milwaukee, WI 53202
USA
Tel: 4142990124
Fax: 4143471977
Email: horizons@new-horizons.org
Internet: http://www.new-horizons.org
Let Them Hear Foundation
1900 University Ave #101
East Palo Alto, CA 94303
Tel: (650)462-3143
Fax: (650)462-3143
Tel: (877)735-2929
Email: info@letthemhear.org
Internet: http://www.letthemhear.org
Fragile X Society
Road End House
6 Stortford Road
Great Dunmow, Essex, CM6 1DA
UK
Tel: 01371 875100
Fax: 01371 859915
Email: info@fragilex.org.uk
Internet: http://www.fragilex.org.uk
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 http://www.rarediseases.org/search/rdblist.html
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: 8/9/2006
Copyright 1988, 1989, 1990, 1991, 1994, 1995, 1997, 1998, 1999, 2006 National Organization for Rare Disorders, Inc.
WebMD Medical Reference from the National Organization of Rare Disorders



