Genetics of antipsychotic drug outcome and implications for the clinician: into the limelight

Figures & data

Table 1 Variability in the distribution of genes (allele frequencies) in different ethnicities^† (15, 16)

	Africans	Asians	European	South American Indians
CYP2D6*1 (EM)	55% (Ethiopian) 52% (Sub-Saharan African)	48% (Japanese)	37% (Northern European)	73%
CYP2D6*3 (PM)	<0.1% (Ethiopians) <0.1% (Sub-Saharan African)	<0.1% (Japanese)	2% (Northern European)	<0.1%
CYP2D6*4 (PM)	3% (Ethiopian) 2% (Sub-Saharan African)	<0.1%	19% (Northern European)	3%
CYP2D6*10 (IM)	6% (African Americans; Ethiopian) 4% (Sub-Saharan African)	39–51%	1–2%	1%
CYP2D6*17 (Altered affinity for substrates of 2D6)	20–35% (African Americans)	<0.1% (Japanese)	<0.1% (Northern European)	<0.1%
CYP2D6*M X N ^†† (Depending on the allele, it represents an increased function) (17)	1.0–2.4% (African Americans) 0.9–16.0% (Black Africans)	0.9–1.3% (East Asians)	0.7–5.6% (Caucasians)	Not determined (Native Americans)

For determination of metabolizer status using *allele combinations, the reader is referred to comprehensive review articles such as that by Mrazek (15).

^†The precise frequencies can differ in small communities due to their geographic locations (15, 18).

^††XN refers to the number of gene copies; for example, CYP2D*1X2 refers to two copies of CYP2D6*1 (17).

Table 2 Distribution of common variant alleles of CYP2C19 (allele frequencies) (21, 30–32))

	Africans	Asian	Europeans (Caucasians)	Native American
CYP2C19*2 (PM)	17%	18–23% (Japanese)	2–15%	12.0–19.1
CYP2C19*3 (PM)	0.4%	5%	0.04%	Not determined
Total PM status:	2–5%	~25%	2–5%	3.3–11.65%
CYP2C19*17 (UM)	18% (Ethiopians)	1.3% (Japanese) 0.64% (Chinese)	18% (Swedes)	Not determined

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