SCIENTIFIC BACKGROUND

ABCA1

Tangier disease is a very rare autosomal recessive disorder of high-density lipoprotein (HDL) metabolism characterized by an absence of mature HDL particles in plasma and lipid deposition in various parenchymal organs. Characteristic features include orange hyperplastic tonsils, splenomegaly, and recurrent neuropathies. Biochemically, plasma is found to contain only pre-β-1-HDL and an almost complete absence of HDL cholesterol (<5 mg/dl), as well as low apoAI, low cholesterol, and triglycerides in the normal range or elevated. Tangier patients have a moderately increased coronary risk.

 

The disease is caused by pathogenic variants in the ABCA1 gene (ATP-binding cassette transporter 1), a membrane protein involved in cholesterol and phospholipid efflux from the cell. Due to ABCA1 dysfunction, nascent HDL particles cannot take up sufficient cholesterol and phospholipids from peripheral cells and are rapidly metabolized. Other monogenic diseases that lead to HDL particle maturation dysfunction and are therefore associated with HDL deficiency (hypoalphalipoproteinemia) (HDL-C < 10 mg/dl) are lecithin-cholesterol acyltransferase (LCAT) deficiency, partial LCAT deficiency (fish eye disease), and apolipoprotein A-I (apo A-I) deficiency. Apo A-I deficiency is also associated with an increased risk of coronary heart disease (CHD).

 

References
Shapiro M.D. 2018, Endotext [Internet] / Hooper et al. 2017, EJHG 25:e1 / Schaefer et al. 2016, Prog. Cardiovasc. Dis. 59:97 / Ramasamy I. 2016, Clin Chim Acta. 454:143 / Schaefer et al. 2016, Endotext [Internet]

GENES

ABCA1

ASSOCIATED TESTS

How to order

LATEST ARTICLES

Exciting news in genetic research! The Human Pangenome Reference Consortium has unveiled an improved version of the human pangenome reference. This c...

Read more

Duchenne muscular dystrophy, a rare inherited muscle disorder characterized by progressive muscle weakness and degeneration that leads to difficultie...

Read more

May 12 is International Nurses Day. It is celebrated on Florence Nightingale’s birthday. She pioneered the field of modern nursing through her dedi...

Read more

Hair loss is a common problem that affects millions of men and women around the world. While genetics is believed to be the most significant factor c...

Read more

Depression is a serious mental health issue affecting over 280 million people worldwide. Recent research has revealed a potential link between gut he...

Read more

If you are unlucky enough to suffer from migraines, you will know that a migraine is not just a bad headache. The headache and accompanying symptoms ...

Read more

Autism spectrum disorder (ASD) is a neurological developmental disorder that affects brain development and function. This affects how people learn, b...

Read more

Researchers have developed a method called "Mendelian Phenotype Search Engine" (MPSE) to identify which sick infants in the neonatal intensive care u...

Read more

Did you know that wisdom teeth are actually an evolutionary leftover from our ancient ancestors that no longer serve their original purpose? These mo...

Read more

Azoospermia is a medical condition characterized by the absence of sperm in the ejaculate and is a major cause of male infertility. It affects 1 in 1...

Read more