CYP2C19 er underkastet genetisk polymorfi og 2- 6% af befolkningen, kaldet dårlige metabolikere (PM’ er), er homozygote for en mutant CYP2C19 allele og mangler derfor et funktionelt CYP2C19 enzym.
CYP2C19 is subject to genetic polymorphism and 2-6% of the population, called poor metabolisers (PMs), are homozygote for a mutant CYP2C19 allele and therefore lacks a functional CYP2C19 enzyme.