familial defective apoprotein B-100
Last reviewed 04/2021
In this genetic hyperlipidaemia cholesterol levels are raised (usually cholesterol 7.5-16 mmol/L) and triglyceride levels are below 2.3 mmol/L. LDL-cholesterol is increased.
In this condition a mutation of apo B intereferes with binding of LDL. The most common cause of this condition is due to a substitution of an amino-acid at position 3500. This mutation has an incidence of approximately 1 in 600 in the general population although it generally does not produce an especially severe hyperlipidaemia.
This is an example of a type IIa hyperlipidaemia according to the Who/Fredrickson classification of primary hyperlipidaemias.
Clinical features are similar to those seen in familial hypercholesterolaemia (FH).
It has been estimated that up to 4% of patients with clinical FH may have familial defective apo B.