Background. Familial defective apolipoprotein (apo) B-100 (FDB) is a common inherited metabolic disorder.
Reduced binding of the apo B-100, the major protein of LDL particles, to LDL receptor results in marked
hypercholesterolemia. FDB is caused particularly by an arginine to glutamine substitution at the codon for amino
acid 3500 of the apo B-100. The aim of this study was to determine mutations potentially responsible for
hypercholesterolemia in the apo B gene and to estimate their frequency in the group of Czech hyperlipidemic patients.
Methods and Results. The groups of 169 unrelated patients with primary isolated hypercholesterolemia (total
cholesterol > 6,5 mmol/l, triglycerides < 2,3 mmol/l) and 58 unrelated patients with combined hyperlipoproteinemia
(total cholesterol > 6,5 mmol/l, triglycerides > 2,3 mmol/l) were screened for mutations in codon 3500 region of the
apolipoprotein B gene by denaturing gradient gel electrophoresis. Mutation R3500Q was detected in 20 patients
with isolated hypercholesterolemia (11,8 %) and in 2 patients with combined hyperlipoproteinemia (3,4 %). No other
mutations were found.
Conclusion. The frequency of FDB in our group of patients with primary isolated hypercholesterolemia is high
when compared with data published in other countries. We suggest that all patients with primary isolated hypercho-
lesterolemia (total cholesterol > 6,5 mmol/l) in the Czech Republic should be analysed for the presence of mutation
R3500Q in the apo B gene.
familial defective apolipoprotein B-100 (FDB), hypercholesterolemia, hyperlipoproteinemia, athe-
rosclerosis, mutation, denaturing gradient gel electrophoresis (DGGE).