Advertisement
Research Article Free access | 10.1172/JCI115839
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Koivisto, U. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Turtola, H. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Aalto-Setälä, K. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Top, B. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Frants, R. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Kovanen, P. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Syvänen, A. in: JCI | PubMed | Google Scholar
Institute of Biotechnology, University of Helsinki, Finland.
Find articles by Kontula, K. in: JCI | PubMed | Google Scholar
Published July 1, 1992 - More info
A mutation of the LDL receptor gene very common among Finnish patients with heterozygous familial hypercholesterolemia (FH) was identified. This mutation, designated as FH-North Karelia, deletes seven nucleotides from exon 6 of the LDL receptor gene, causes a translational frameshift, and is predicted to result in a truncated receptor protein. Only minute quantities of mRNA corresponding to the deleted gene were detected. Functional studies using cultured fibroblasts from the patients revealed that the FH-North Karelia gene is associated with a receptor-negative (or binding-defective) phenotype of FH. Carriers of the FH-North Karelia gene showed a typical xanthomatous form of FH, with mean serum total and LDL cholesterol levels of 12 and 10 mmol/liter, respectively. This mutation was found in 69 (34%) out of 201 nonrelated Finnish FH patients and was especially abundant (prevalence 79%) in patients from the eastern Finland. These results, combined with our earlier data on another LDL receptor gene deletion (FH-Helsinki), demonstrate that two "Finnish-type" mutant LDL receptor genes make up about two thirds of FH mutations in this country, reflecting a founder gene effect. This background provides good possibilities to examine whether genetic heterogeneity affects the clinical presentation or responsiveness to therapeutic interventions in FH.
Images.