The mechanism causing influenza-virus-associated encephalopathy is unclear, even though diclofenac metabolites may induce this pathogenesis. CYP2C9 is known as the major cytochrome P450 gene product that catalyzes diclofenac in human liver. It is uncertain whether the mutation of CYP2C9 is associated the pharmacologic effects of diclofenac in influenza infection. Therefore, we applied a simple and rapid procedure involving real-time fluorescence allele-specific PCR(TaqMan-ASA) assay and denaturing HPLC assay to detect the mutation of CYP2C9 gene. A single-base mutation in the CYP2C9 gene was found in one of thirty subjects in the healthy population. We suggest that this mutation in the CYP2C9 gene may be related to diclofenac-induced influenza-virus-associated encephalopathy.

*1Division of Molecular Diagnostics, Department of Clinical Medicine, Tohoku University, School of Medicine, Sendai 980-8574

【Key Words】influenza-virus-associated encephalopathy, diclofenac, CYP2C9 polymorphism, single nucleotide polymorphisms: SNPs