Table 2.

The CPIC Assignment of likely CYP2C9 Phenotype based on Genotype (2020)

Likely phenotypea,bActivity scoreGenotypeExamples of diplotype
Normal metabolizer2An individual with 2 normal function alleles*1/*1
Intermediate metabolizer1.5
1		An individual with one normal function allele plus one decreased function allele; OR
one normal function allele plus one no function allele
OR
2 decreased function alleles		*1/*2
*1/*3
*2/*2
Poor metabolizer0.5
0		An individual with one no function allele plus one decreased function allele; OR
2 no function alleles		*2/*3
*3/*3
Indeterminaten/aAn individual with allele combinations with uncertain or unknown function alleles*1/*7
*1/*10
*7/*10
*1/*58

This CPIC table has been adapted from (27). Additional information on allele function is available from PharmVar and CPIC.

From: Dronabinol Therapy and CYP2C9 Genotype

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