$Unique_ID{BRK03745} $Pretitle{} $Title{Floating-Harbor Syndrome} $Subject{Floating-Harbor Syndrome FHS Dubowitz Syndrome Russell-Silver Syndrome Three M Syndrome} $Volume{} $Log{} Copyright (C) 1993 National Organization for Rare Disorders, Inc. 934: Floating-Harbor Syndrome ** IMPORTANT ** It is possible that the main title of the article (Floating-Harbor Syndrome) is not the name you expected. Please check the SYNONYMS listing to find the alternate name and disorder subdivisions covered by this article. Synonyms FHS Information on the following diseases can be found in the Related Disorders section of this report: Dubowitz Syndrome Russell-Silver Syndrome Three M Syndrome General Discussion ** REMINDER ** The Information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Floating-Harbor Syndrome is a very rare disorder characterized by short stature, delayed language skills, and a triangular shaped face. A broad nose, deep-set eyes and a wide mouth with thin lips give the affected patient a distinct appearance. FHS was named for the first two patients who were seen at Boston Floating Hospital and Harbor General Hospital in California. The cause of this disorder is not known. Symptoms Floating-Harbor Syndrome is a very rare disorder in which the affected patient has short stature with delayed bone growth, a delay in expressive language, and distinct facial features. Growth may be affected prenatally but typically becomes apparent during the first year of life. All patients with FHS have a delay in bone age which means that the rate of growth and development of the bones is slower than normal. The limbs and trunk are in proportion while the head may appear relatively large. Delayed expressive language is found in all patients with FHS. Some children may be delayed in their learning ability as well. Most children appear to be slightly behind in school but there have been no recorded cases of moderate or severe retardation. Distinctive facial features are another symptom of Floating-Harbor Syndrome. These features typically become apparent at the age of three or four years. The nose and nasal bridge are broad, and the mouth is wide with thin lips. The eyes are deeply set and the face appears small with a triangular shape. Eyelashes may be longer than normal, and there may be dental abnormalities. Abnormal bending (clinodactyly) of the fifth finger, clubbing of the fingers and/or excessive body hair (hirsutism) have been found in some patients with Floating-Harbor Syndrome. An intestinal malabsorption disorder caused by intolerance to gluten (Celiac Sprue) has been found in several patients with this disorder. (For more information on this disorder choose "Celiac Sprue" as your search term in the Rare Disease Database). An additional thumb, constipation and/or a narrowing of the opening of the right ventricle into the pulmonary artery (pulmonary stenosis) have also been found in several affected patients. Causes The exact cause of Floating-Harbor Syndrome is not known. There have been no reported cases of reccurence within a family. It is thought that FHS may be a new dominant mutation. A mutation is an unusual change in genetic material that has occurred for no apparent reason. The alteration changes the original expression of the gene. When a mutation occurs it can be transmitted to future generations. Affected Population Floating-Harbor Syndrome is a very rare disorder that affects males and females in equal numbers. There have been approximately twenty cases of this disorder reported in the medical literature. It is thought that the incidence of this disorder may actually be higher because many cases go unrecognized. Related Disorders Symptoms of the following disorders can be similar to those of Floating- Harbor Syndrome. Comparisons may be useful for a differential diagnosis: Dubowitz Syndrome is a rare disorder thought to be inherited as an autosomal recessive genetic trait. Symptoms of this disorder are apparent at birth. Short stature, dental abnormalities, low birth weight, and/or unusual facial features are characteristic of Dubowitz Syndrome. (For more information on this disorder, choose "Dubowitz Syndrome" as your search term in the Rare Disease Database). Russell-Silver Syndrome is a rare disorder commonly thought of as a type of dwarfism. People with this disorder are short with a small triangular- shaped face, and light brown spots on the skin. Developmental abnormalities, as well as abnormal curvature of the fifth finger, may also be present. The exact cause of Russell-Silver Syndrome is not known although some medical researchers believe it may be inherited as either an X-linked or dominant genetic trait with incomplete penetrance. (For more information on this disorder, choose "Russell-Silver Syndrome" as your search term in the Rare Disease Database). Three M Syndrome is a rare disorder characterized by low birth weight, short stature, narrow face, abnormal bending of the fingers (clinodactyly), and thin-slender long bones. The head appears to be large and the face has a triangular shape. A prominent mouth as well as a short neck are also features of this disorder. Three M Syndrome is inherited as an autosomal recessive genetic trait. Therapies: Standard Patients with Floating-Harbor Syndrome will benefit from an educational environment that provides appropriate programs to assist their needs. Speech therapy as well as teachers trained to work with learning disabilities will be of benefit. Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive. Therapies: Investigational Research on birth defects and their causes is ongoing. The National Institutes of Health (NIH) is sponsoring the Human Genome Project which is aimed at mapping every gene in the human body and learning why they sometimes malfunction. It is hoped that this new knowledge will lead to prevention and treatment of genetic disorders in the future. This disease entry is based upon medical information available through January 1993. 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. Resources For more information on Floating Harbor Syndrome, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 Floating-Harbor Syndrome Support Group 27 Hatfield Road Dagenham Essex, RM9 6JR The National Arthritis and Musculoskeletal and Skin Diseases Information Clearinghouse Box AMS Bethesda, MD 20892 (301) 495-4484 Human Growth Foundation (HGF) 7777 Leesburg Pike P.O. Box 3090 Falls Church, VA 22043 (703) 883-1773 Short Stature Foundation 17200 Jamboree Rd., Suite J Irvine, CA 92714-5828 (714) 474-4554 (800) 24-DWARF Association for Research into Restricted Growth 2 Mount Court 81 Central Hill London SE 19 1BS England For Genetic Information and Genetic Counseling Referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 10th Ed.: Victor A. McKusick, Editor: Johns Hopkins University Press, 1990. Pp. 398. FLOATING-HARBOR SYNDROME: M.A. Patton, et al.; J Med Genet (1991, issue 28). Pp. 201-204. FLOATING-HARBOR SYNDROME AND CELIAC DISEASE: A.E. Chudley, et al.; Am J Med Genet (March 15, 1991, issue 38(4)). Pp. 562-4.