Eight novel LDL receptor gene mutations among patients under LDL apheresis in Dresden and Leipzig.

LDL apheresis is highly efficient in reducing elevated plasma cholesterol. Due to strict indications only patients with severe, refractory hypercholesterolemia are treated with this method. Mutations in the LDL receptor gene are major genetic causes for severe hypercholesterolemia. Screening the entire gene in LDL apheresis patients from Saxony should determine whether an increased frequency of defined mutations is responsible for the atherogenic hypercholesterolemia in this group. 31 unrelated patients (15 male, 16 female, age 33-71 yrs.) were included in the analysis. The LDL-R gene was screened using SSCP and/or automated sequencing. The familial defective apolipoprotein B-100 (FDB) mutation was genotyped using established PCR techniques. Nineteen of 31 patients were carriers of an LDL-R mutation. Ten missense and two nonsense mutations, three insertions and two deletions were detected. The mutations C74S, C74R, T87M, 660delC, 662insCCCCG, 680insGGACAAATCTGA, 1428insC and 2167delG have not been previously described. One patient was compound heterozygous for two missense mutations. Two further patients were heterozygous for FDB. No mutations were found among controls. A genetic background for hypercholesterolemia in the LDL-R could be established in about 61% of the patients examined. Therefore, methods of DNA analysis allow to recognize and adequately treat a large portion of high-risk individuals at an early stage. Copyright 2001 Wiley-Liss, Inc.