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Williams syndrome is a developmental disorder that affects many parts of the body. This condition is characterized by mild to moderate mental retardation or learning disabilities, unique personality characteristics, distinctive facial features, and heart and blood vessel (cardiovascular) problems.
Most people with Williams syndrome have some degree of mental retardation. They typically do better on tasks that involve spoken language and memorization than on visual-spatial tasks such as writing and drawing. Affected individuals have outgoing, engaging personalities and tend to take an extreme interest in other people. Attention deficit disorder (ADD), problems with anxiety, and phobias are common among people with this disorder.
Young children with Williams syndrome have distinctive facial features including a broad forehead, a short nose with a broad tip, full cheeks, a wide mouth with full lips, and small, widely spaced teeth. In older children and adults, the face appears longer and gaunt.
A form of cardiovascular disease called supravalvar aortic stenosis (SVAS) occurs frequently in people with Williams syndrome. Supravalvar aortic stenosis is a narrowing of the large blood vessel that carries blood from the heart to the rest of the body (the aorta). If this condition is not treated, the aortic narrowing can lead to shortness of breath, chest pain, and heart failure. Other problems with the heart and blood vessels, including high blood pressure (hypertension), have also been reported in people with Williams syndrome.
Additional signs and symptoms of Williams syndrome include abnormalities of connective tissue (tissue that supports the body's joints and organs) such as joint problems and soft, loose skin. Affected people may also have increased calcium levels in the blood (hypercalcemia) in infancy, developmental delays, problems with coordination, and short stature. Medical problems involving the eyes and vision, the digestive tract, and the urinary system are also possible.
An estimated 1 in 7,500 to 20,000 people is born with Williams syndrome.
Williams syndrome is related to chromosome 7.
The CLIP2, ELN, GTF2I, GTF2IRD1, LIMK1, and NCF1 genes are associated with Williams syndrome.
Williams syndrome is caused by the deletion of genetic material from a specific region of chromosome 7. The deleted region includes more than 20 genes, and researchers believe that a loss of several of these genes probably contributes to the characteristic features of this disorder.
CLIP2, ELN, GTF2I, GTF2IRD1, and LIMK1 are among the genes that are typically deleted in people with Williams syndrome. Researchers have found that loss of the ELN gene is associated with the connective tissue abnormalities and cardiovascular disease (specifically supravalvar aortic stenosis) found in many people with this disease. Studies suggest that deletion of LIMK1, GTF2I, GTF2IRD1, and perhaps other genes may help explain the characteristic difficulties with visual-spatial tasks. Loss of the GRF2IRD1 may also be partly responsible for the distinctive facial features often associated with Williams syndrome. Additionally, there is evidence that the deletion of several of these genes, including CLIP2, may contribute to the unique behavioral characteristics, mental retardation, and other cognitive difficulties seen in this condition.
The NCF1 gene is also deleted in some people with Williams syndrome. Researchers have found that the loss of this gene appears to lower the risk of developing hypertension in some affected individuals.
The relationship between other genes in the deleted region of chromosome 7 and the signs and symptoms of Williams syndrome is unknown.
Most cases of Williams syndrome are not inherited, but occur as random events during the formation of reproductive cells (eggs or sperm) in a parent of an affected individual. These cases occur in people with no history of the disorder in their family.
Williams syndrome is considered an autosomal dominant condition because one copy of the altered chromosome 7 in each cell is sufficient to cause the disorder. In a small percentage of cases, people with Williams syndrome inherit the chromosomal deletion from a parent with the condition.
'''Williams syndrome''' ('''Williams-Beuren syndrome''') is a rare genetic disorder, occurring in fewer than 1 in every 20,000 live births. It is characterized by a distinctive, "elfin" facial appearance, an unusually cheerful demeanor, ease with strangers, mental retardation coupled with an unusual facility with language, a love for music, cardiovascular problems such as supravalvular aortic stenosis, and hypercalcemia. Williams shares some features with autism, although persons with Williams syndrome generally possess very good social skills, to the point that this condition is sometimes called "cocktail party syndrome". Most persons with Williams syndrome are missing about 21 genes on chromosome 7, including the gene for the production of elastin. Inability to produce this protein is likely the root of cardiovascular problems in this syndrome, and may be responsible for differences in brain development as well. Another symptom of Williams syndrome is lack of depth perception and inability to visualize how different parts assmble into larger objects (for example: assembling a jigsaw puzzle). This problem is caused by a slight defect in the brain that creates a sparsity of of tissue in the visual systems of the brain. A team of researchers at the National Institute of Mental Health used functional magnetic resonance imaging (fMRI) to watch the blood flow of the brains of test subjects while they were performing two tasks involving spatial relations. Persons with Williams syndrome showed weaker activity in the section of the brain associated with spatial relations. Scans of brain anatomy of test subjects with Williams indicated a deficit of brain tissue in an area of the same section of the brain mentioned above. This deficit partially blocks transmission of visual information to the spatial relations region of the brain. In the test, all participants of the study measured in the average intelligence ... [ Read More ]
Irritable Bowel Syndrome and the Mind-Body Connection - Authored by William B. Salt II, MD. A method for healing combining science with a mind, body, spirit approach.
Williams Syndrome and Prader-Willi Syndrome - Diagnostic assessment, selected treatment services and opportunities to participate in research from the Yale University Child Study Center.
Williams Syndrome Foundation - Seeks to create or enhance opportunities in education, housing, employment and recreation for people who have Williams Syndrome and other related or similar conditions.
Williams Syndrome Association - A rare genetic condition (estimated to occur in 1/20,000 births) which causes medical and developmental problems.
National Library of Medicine - A list of synonyms of Williams syndrome, a summary and major features.
Williams Syndrome - About the author's daughter, Sereena Celeste Beech, who has this syndrome.
A Music Camp for Those Afflicted but Gifted, Too - New York Times feature article about the Belvoir Terrace summer music camp program for people with Williams syndrome.
Williams Syndrome Association of Ireland - Provides information on the condition and on the Irish WS association. Current news, events, and fundraising.
NORD : Williams Syndrome - Offers alternative names, a general discussion and resources.
Moylan Family Website - An Irish family's experience of Williams Syndrome.