Tangier disease

autorecessive

Tangier disease

Tangier disease, also known as familial alpha-lipoprotein deficiency, is a rare inherited disorder characterized by a severe reduction in the amount of high-density lipoprotein (HDL) in the blood. HDL is often referred to as "good cholesterol" because it helps remove excess cholesterol from the bloodstream. The disease is named after Tangier Island in Virginia, where the first identified cases were discovered.

Genetics

Tangier disease is caused by mutations in the ABCA1 gene, which provides instructions for making a protein that is essential for the formation of HDL. The ABCA1 protein plays a critical role in the transport of cholesterol and phospholipids across cell membranes. Mutations in this gene lead to the accumulation of cholesterol in various tissues, including the tonsils, spleen, liver, and bone marrow.

Symptoms

Individuals with Tangier disease often present with:

• Enlarged, orange-colored tonsils
• Hepatosplenomegaly (enlarged liver and spleen)
• Peripheral neuropathy (nerve damage)
• Atherosclerosis (build-up of fats, cholesterol, and other substances in and on the artery walls)
• Corneal opacities (clouding of the cornea)

Diagnosis

Diagnosis of Tangier disease is typically based on clinical findings, family history, and laboratory tests showing very low levels of HDL cholesterol. Genetic testing can confirm the diagnosis by identifying mutations in the ABCA1 gene.

Treatment

There is currently no cure for Tangier disease. Treatment focuses on managing symptoms and reducing the risk of complications. This may include:

• Dietary modifications to reduce cholesterol intake
• Medications to manage cholesterol levels and prevent atherosclerosis
• Regular monitoring and supportive care for neuropathy and other symptoms

Epidemiology

Tangier disease is extremely rare, with only a few hundred cases reported worldwide. It affects both males and females equally and can occur in any ethnic group.

See also

• High-density lipoprotein
• Cholesterol
• Atherosclerosis
• Peripheral neuropathy
• Genetic disorder