Mutations in the low-density lipoprotein receptor gene in Swedish familial hypercholesterolaemia patients: clinical expression and treatment response.

Background: Familial hypercholesterolaemia, an autosomal co-dominant disorder caused by defects in the low-density lipoprotein receptor gene, is strongly associated with premature development of cardiovascular disease.

Methods: In this study, we have applied a gene screening method in a population of familial hypercholesterolaemia patients in order to describe the genetic background of the disease in southern Sweden. These patients were studied with the aim of relating the presence of the different mutations to the clinical expression of the disease and to the response to pharmacological treatment.

Results: In 16 out of 21 patients, potentially disease-causing low-density lipoprotein receptor gene defects were found, including five not previously described alterations (C240-->F, C122-->stop, C356-->Y, 785insG, 165delG). No defects in apolipoprotein B were found. One group of patients (n = 4) carried the mutation C122-->stop and another group of patients (n = 4) a mutation causing the substitution W66-->G. Patients in the two genotype subgroups were very similar with respect to lipid levels before treatment.

Conclusion: A tendency towards differential susceptibility to treatment with statins was observed for the patient groups, encouraging further comparative studies of heterozygous FH patients.