Stargardt macular degeneration is a genetic eye disorder that causes progressive vision loss. This disorder affects the retina, the specialized light-sensitive tissue that lines the back of the eye. Specifically, Stargardt macular degeneration affect READ MORE

Steatocystoma multiplex is a skin disorder characterized by the development of multiple noncancerous (benign) cysts known as steatocystomas. These growths begin in the skin's sebaceous glands, which normally produce an oily substance called sebum tha READ MORE

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a severe skin reaction most often triggered by particular medications. Although Stevens-Johnson syndrome and toxic epidermal necrolysis were once thought to be separate conditions, they READ MORE

Stickler syndrome is a group of hereditary conditions that are characterized by a distinctive facial appearance, eye abnormalities, hearing loss, and joint problems. These signs and symptoms vary widely among affected individuals, even among members READ MORE

STING-associated vasculopathy with onset in infancy (SAVI) is a disorder involving abnormal inflammation throughout the body, especially in the skin, blood vessels, and lungs. Inflammation normally occurs when the immune system sends signaling molecu READ MORE

Stormorken syndrome is a rare condition that affects many body systems. Affected individuals usually have thrombocytopenia, in which there are abnormally low numbers of blood cells called platelets. Platelets are involved in normal blood clotting; a READ MORE

Sturge-Weber syndrome is a condition that affects the development of certain blood vessels, causing abnormalities in the brain, skin, and eyes from birth. Sturge-Weber syndrome has three major features: a red or pink birthmark called a port-wine birt READ MORE

Stüve-Wiedemann syndrome is a severe condition characterized by bone abnormalities and dysfunction of the autonomic nervous system, which controls involuntary body processes such as the regulation of breathing rate and body temperature. The condition READ MORE

STXBP1 encephalopathy is a condition characterized by abnormal brain function (encephalopathy) and intellectual disability. Most affected individuals also have recurrent seizures (epilepsy). The signs and symptoms of this condition typically begin in READ MORE

Subcortical band heterotopia is a condition in which nerve cells (neurons) do not move (migrate) to their proper locations in the fetal brain during early development. (Heterotopia means "out of place.") Normally, the neurons that make up the outer s READ MORE

Succinic semialdehyde dehydrogenase deficiency is a disorder that can cause a variety of neurological problems. People with this condition typically have developmental delays, especially in speech development; intellectual disabilities; and decreased READ MORE

Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is an inherited disorder that impairs the body's ability to break down ketones, which are molecules produced in the liver during the breakdown of fats. The signs and symptoms of SCOT deficienc READ MORE