Tangier disease is an inherited disorder characterized by significantly reduced levels of high-density lipoprotein (HDL) in the blood. HDL transports cholesterol and certain fats called phospholipids from the body's tissues to the liver, where they are removed from the blood. HDL is often referred to as "good cholesterol" because high levels of this substance reduce the chances of developing heart and blood vessel (cardiovascular) disease. Because people with Tangier disease have very low levels of HDL, they have a moderately increased risk of cardiovascular disease.
Additional signs and symptoms of Tangier disease include a slightly elevated amount of fat in the blood (mild hypertriglyceridemia); disturbances in nerve function (neuropathy); and enlarged, orange-colored tonsils. Affected individuals often develop atherosclerosis, which is an accumulation of fatty deposits and scar-like tissue in the lining of the arteries. Other features of this condition may include an enlarged spleen (splenomegaly), an enlarged liver (hepatomegaly), clouding of the clear covering of the eye (corneal clouding), and type 2 diabetes.
Tangier disease is a rare disorder with approximately 100 cases identified worldwide. More cases are likely undiagnosed. This condition is named after an island off the coast of Virginia where the first affected individuals were identified.
Mutations in the ABCA1 gene cause Tangier disease. This gene provides instructions for making a protein that releases cholesterol and phospholipids from cells. These substances are used to make HDL, which transports them to the liver.
Mutations in the ABCA1 gene prevent the release of cholesterol and phospholipids from cells. As a result, these substances accumulate within cells, causing certain body tissues to enlarge and the tonsils to acquire a yellowish-orange color. A buildup of cholesterol can be toxic to cells, leading to impaired cell function or cell death. In addition, the inability to transport cholesterol and phospholipids out of cells results in very low HDL levels, which increases the risk of cardiovascular disease. These combined factors cause the signs and symptoms of Tangier disease.
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
Other Names for This Condition
- A-alphalipoprotein Neuropathy
- alpha High Density Lipoprotein Deficiency Disease
- Cholesterol thesaurismosis
- Familial High Density Lipoprotein Deficiency Disease
- Familial Hypoalphalipoproteinemia
- HDL Lipoprotein Deficiency Disease
- Lipoprotein Deficiency Disease, HDL, Familial
- Tangier Disease Neuropathy
- Tangier Hereditary Neuropathy
Additional Information & Resources
Genetic Testing Information
Genetic and Rare Diseases Information Center
Research Studies from ClinicalTrials.gov
Catalog of Genes and Diseases from OMIM
Scientific Articles on PubMed
- Iatan I, Alrasadi K, Ruel I, Alwaili K, Genest J. Effect of ABCA1 mutations on risk for myocardial infarction. Curr Atheroscler Rep. 2008 Oct;10(5):413-26. Review. Citation on PubMed
- Kolovou GD, Mikhailidis DP, Anagnostopoulou KK, Daskalopoulou SS, Cokkinos DV. Tangier disease four decades of research: a reflection of the importance of HDL. Curr Med Chem. 2006;13(7):771-82. Review. Citation on PubMed
- Koseki M, Matsuyama A, Nakatani K, Inagaki M, Nakaoka H, Kawase R, Yuasa-Kawase M, Tsubakio-Yamamoto K, Masuda D, Sandoval JC, Ohama T, Nakagawa-Toyama Y, Matsuura F, Nishida M, Ishigami M, Hirano K, Sakane N, Kumon Y, Suehiro T, Nakamura T, Shimomura I, Yamashita S. Impaired insulin secretion in four Tangier disease patients with ABCA1 mutations. J Atheroscler Thromb. 2009 Jun;16(3):292-6. Epub 2009 Jun 25. Citation on PubMed
- Maxfield FR, Tabas I. Role of cholesterol and lipid organization in disease. Nature. 2005 Dec 1;438(7068):612-21. Review. Citation on PubMed
- Nofer JR, Remaley AT. Tangier disease: still more questions than answers. Cell Mol Life Sci. 2005 Oct;62(19-20):2150-60. Review. Citation on PubMed
- Probst MC, Thumann H, Aslanidis C, Langmann T, Buechler C, Patsch W, Baralle FE, Dallinga-Thie GM, Geisel J, Keller C, Menys VC, Schmitz G. Screening for functional sequence variations and mutations in ABCA1. Atherosclerosis. 2004 Aug;175(2):269-79. Citation on PubMed
- Soumian S, Albrecht C, Davies AH, Gibbs RG. ABCA1 and atherosclerosis. Vasc Med. 2005 May;10(2):109-19. Review. Citation on PubMed
- Stefková J, Poledne R, Hubácek JA. ATP-binding cassette (ABC) transporters in human metabolism and diseases. Physiol Res. 2004;53(3):235-43. Review. Citation on PubMed
- Tall AR, Yvan-Charvet L, Terasaka N, Pagler T, Wang N. HDL, ABC transporters, and cholesterol efflux: implications for the treatment of atherosclerosis. Cell Metab. 2008 May;7(5):365-75. doi: 10.1016/j.cmet.2008.03.001. Review. Citation on PubMed
- Tang C, Oram JF. The cell cholesterol exporter ABCA1 as a protector from cardiovascular disease and diabetes. Biochim Biophys Acta. 2009 Jul;1791(7):563-72. doi: 10.1016/j.bbalip.2009.03.011. Epub 2009 Apr 1. Review. Citation on PubMed