Tangier Disease
Sequencing of the ABCA1 gene

Genes
(full coding
region):		  ABCA1
Lab method: NGS
TAT: 6-9 weeks
Specimen requirements: 2-4 ml of blood with anticoagulant EDTA

1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker.
Ordering information: Go to online ordering or download sample submission form

Indications for genetic testing:
1. Confirmation of clinical diagnosis
2. Differential diagnosis
3. Genetic counceling

Tangier disease is characterised by hypocholesterolaemia, extremely low or absent level of HDL cholesterol, modestly decreased LDL cholesterol and elevated triglycerides in plasma.

The major clinical signs of Tangier disease include hyperplastic yellow-orange tonsils, hepatosplenomegaly, and peripheral neuropathy. Rarer complications may include corneal opacities that typically do not affect vision, premature atherosclerotic coronary artery disease, and mild hematologic manifestations, such as mild thrombocytopenia, reticulocytosis, stomatocytosis, or hemolytic anemia.

Tangier disease is inherited in an autosomal recessive manner. Tangier disease is caused by variants in the ABCA1 gene. Global prevalence of the disease is 1:640 000.

References:
Assmann G et al 2001. Familial analphalipoproteinemia: Tangier disease. In: Scriver CR, Beaudet AL, Sly WS, Valle D, Vogelstein B, eds. The Metabolic and Molecular Bases of Inherited Disease. 8 ed. Vol 2. New York, NY: McGraw-Hill; 2001:2937-80.
Burnett JR et al 2019. Tangier Disease. GeneReviews® [Internet]. November 21, 2019.
Hooper AJ et al 2017. Clinical utility gene card for: Tangier disease. European Journal of Human Genetics volume 25, pagese1–e3(2017).