SNP Shot: Genomic Insights

Familial HDL deficiency is a medical condition defined by abnormally low amounts of high-density lipoprotein (HDL) in the bloodstream. HDL, often called "good cholesterol," plays a vital role in transporting cholesterol and phospholipids from the body's tissues to the liver. The liver then processes and either redistributes these substances or eliminates them. Sufficient HDL levels are associated with a lower risk of cardiovascular disease, while individuals with familial HDL deficiency may experience heart problems at an earlier age, often before 50.

A related, more severe condition, Tangier disease, also presents with extremely low HDL levels. However, Tangier disease is distinguished by additional symptoms not seen in familial HDL deficiency, including nerve dysfunction, enlarged and discolored tonsils (orange), and corneal clouding.

Inheritance:

Familial HDL deficiency follows an autosomal dominant inheritance pattern. This means that a change (alteration) in just one copy of either the ABCA1 or APOA1 gene within each cell is enough to cause the condition. In contrast, Tangier disease develops when both copies of the ABCA1 gene are altered.