Effect of polymorphisms in the CYP2C9 gene on valproic acid levels in the blood of women’s in a reproductive age with epilepsy

On the level of antiepileptic drugs (AEDs) in the blood, affect individual genetically determined features of the human metabolism. The purpose: the study of the effect of SNPs CYP2C9 gene cytochrome P450 2C9 isoenzyme liver concentrations of valproic acid (VA) in the blood of women`s in a reproductive age with epilepsy and taking as the main AED — valproate. Methods: The study of the concentration of valproic acid in the blood plasma, and molecular genetic testing polymorphisms in the gene CYP2C9. Results: Frequency cumulation VA in the blood of carriers CYP2C9*2/CYP2C9*3 was 8 times higher for heterozygous carriers of polymorphism CYP2C9*2 — 2.6 times higher than for heterozygous carriers and CYP2C9*3 is 3 times higher than the homozygous polymorphism CYP2C9*1. Conclusions: The decrease in activity 2C9 isoenzyme cytochrome P450 liver in carriers of polymorphic allelic variants CYP2C9*2 and CYP2C9*3 requires individual titration of drugs VA to reduce the risk of adverse side effects and the risk of dose-related teratogenesis.

epilepsy, woman, reproductive age, pharmacogenetics, valproic acid, CYP2C9, gene single nucleotide polymorphism, therapeutic drug monitoring, teratogenesis

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