Molecular genetics and clinical features of Japanese patients with familial hypercholesterolemia

Familial hypercholesterolemia (FH) is a common genetic hyperlipidemia in Japan as well as in other countries. We have found 11 mutants of LDL-receptor gene, which account for 40% of our FK series, while in the remaining 60% the LDL-receptor gene mutants were still unknown. Thus, LDL-receptor gene mutations are highly heterogenous in Japanese FH patients, but K790X is a common mutant (about 20% in our FH patients). Familial defective apolipoprotein B (FDB) were never found in Japanese FH patients. Clinical features of FH, including responses to drugs, are partially dependent on LDL-receptor genotype. For the treatment of coronary heart disease in FH heterozygotes, LDL-apheresis is effective, and may become the therapy of choice in severe type of FH.