Association betweencytochrome P4503A4 genotype polymorphism and drug-resistant epilepsy

：Objective To investigatethe distribution of single nucleotide polymorphisms (SNPs) in three down - regulatedCYP3A4 enzymes of cytochrome P4503A4 (CYP3A4) , and to explore their association withdrug-resistant epilepsy in Southern Han Chinese. Methods Polymerase chainreactionrestriction fragment length polymorphism (PCR-RFLP) method was used to detect thedistribution of three SNPs (CYP3A4*4, CYP3A4*5 and CYP3A4*6) in 112 drug-resistantepilepsy cases (resistance group), and in 136 healthy people(control group). Thedifference in CYP3A4 genotype between two groups was analyzed.Results CYP3A4*4 andCYP3A4*6 were wildtype genotypes in all the cases and healthy people. CYP3A4*5 was awild-type genotype in all the control people and 108 resistance group cases, except that 4cases in the resistant group appeared to have heterozygotic CYP3A4*5. Difference betweentwo groups was significant [136:0 vs 108: 4, OR(95%CI)=1.037(1.001-1.075), P=0.040].Conclusion CYP3A4*5 polymorphism may be associated to drug-resistance in epilepsy.