A genetic disorder characterized by mild mental retardation, unique personality characteristics, unusual facial features, and cardiovascular disease. The level of calcium tends to be high in blood (hypercalcemia) and urine (hypercalciuria).
Mental retardation is the rule and ranges from severe to mild. Personality features include overfriendliness, general anxiety, and attention deficit disorder. Facial features include narrow forehead, fullness about the eyes, short nose, flat midface, full lips, wide mouth, small jaw, and prominent earlobes. Supravalvar aortic stenosis (narrowing of the aorta just above the valve) is the most common and important cardiovascular abnormality.
Williams syndrome is inherited in an autosomal dominant manner and is due to a small chromosome deletion. Most cases are new occurrences but parent-to-child transmission is known. The region deleted is from chromosome 7 (band 7q11) and includes the ELN (elastic) gene, a useful molecular marker in tests to detect the deletion. The syndrome is due not merely to the loss of ELN but to contiguous gene deletion, loss of a series of adjacent genes.
- Willis, circle of
A critical arterial circle at the base of the brain. The circle of Willis receives all the blood that is pumped up the two internal carotid arteries that come up the front of the neck. All the principal arteries that supply the two halves of the brain (hemispheres) branch off from the circle of Willis.
- Wilms tumor
A childhood form of kidney cancer with a peak age of occurrence at 3 years of age. It is sometimes associated with abnormalities of the urinary tracts or other birth defects. Some cases are related to defects in one of two genes referred to as Wilms’ tumor 1 (WT1) or Wilms’ tumor 2 (WT2). Symptoms […]
- Wilson disease
An inherited disorder of copper metabolism that results in an abnormal accumulation of copper in the body. Although the accumulation of copper begins at birth, symptoms of the disorder do not appear until later in life, between the ages of 6 and 40. A diagnostic feature of the disease is a Kayser-Fleischer ring, a deep […]
Women. A late 20th century creation. A feminist spelling to avoid the suffix men.
The trachea, a tube-like portion of the respiratory (breathing) tract that connects the larynx (the voice box) with the lungs. Each time we inhale (breathe in), air goes into our nose or mouth, then through the larynx, down the trachea, and into our lungs. When we exhale (breathe out), the air goes out the other […]