Inconsistency in race and ethnic classification in pharmacogenetics studies and its potential clinical implications

Figures & data

Figure 1 Chart of ethnic categories which fall under the NIH term of “Asian”.

Note: Data from references ⁷, ⁸, ¹⁰, ¹², ¹⁴, ¹⁶, ²⁸, ³⁷, ⁴¹, ⁴², ⁴⁸, ⁵¹, ^71–73, ^87–90.

Figure 2 Chart of ethnic categories which fall under the NIH term of “Caucasian”.

Note: Data from references ⁹, ¹¹, ¹³, ¹⁸, ^20–26, ²⁸, ³⁴, ³⁷, ^42–45, ⁷⁰, ⁷⁵, ⁸⁷, ^91–94, ¹²⁸.

Figure 3 Chart of ethnic categories which fall under the NIH term of “Black”.

Note: Data from references ¹¹, ¹⁵, ¹⁶, ¹⁹, ^26–33, ^35–37, ⁴⁰, ⁴⁶, ⁴⁷, ⁴⁹, ⁵⁰, ⁷⁰, ⁷⁵, ⁷⁹, ⁸⁷, ^94–97, ¹²⁹, ¹³⁰.

Table 2 Allele frequency data for ethnic categories which showed a significant deviation from CPIC categories

Ethnicity	CYP2C9 allele frequency (%)		CYP2C19 allele frequency (%)			CYP2D6 Allele Frequency (%)		References
Asian	*2	*3	*2	*3	*17	*4	*17
CPIC East Asian	0.1	3.4	29.0	8.3	1.3	0.7	<0.1	^Citation87
Hui Chinese	4.6		49.4	5.2				^Citation88
Han Chinese			38.6	5.2				^Citation88
North Asian			18.5	4.4				^Citation70
Orang Asli			5.7	6.5	4.8			^Citation90
CPIC South Asian	10.7	10.2	34.3	0.9	17.3	7.9	0.1	^Citation87
Sinhalese	10.2	5.1	44.7	0				^Citation89
Tamils	10.6	2.8	38.2	1.4				^Citation89
Moors	9.2	2.0	31.0	0				^Citation89
Caucasian
CPIC Caucasian (European and North American)	12.6	7.1	14.6	0.6	21.3	18.1	0.3	^Citation87
Laks		19.5						^Citation91
Avars		15.5						^Citation91
Dargins		16.0						^Citation91
Dutch	11	20	13.3–14	0.0–0.2	20	18.4	0	^Citation75,Citation128
South African Caucasian	10	36	13	1	18		3	^Citation75
Polish	11	1	15	0	36		0	^Citation75
Czech	19	7	8	0	29		0	^Citation75
Slovakian	7	4	19	2	33			^Citation75
Mediterannean-South European			12.5	0.1	42.0		2.0	^Citation70
Faroese	8.8	5.3	18.8	0	15.4	33.4		^Citation93
Cypriot	19	7	21	4	11		40	^Citation75
German	12	5	17	0	21		10	^Citation75
CPIC Middle Eastern	13.2	9.3	13.2	2.3	21.6	7.8	1.6	^Citation87
Yemenite Jewish	5.1	8.1						^Citation92
Black
CPIC African American	2.4	1.0	14.5	0.7	15.4	3.3	20.0	^Citation87
CPIC African	2.3	1.2	18.3	0.3	20	6.4	18.1	^Citation87
Ethiopian	7.7–14.7	6.0–12.4	13.6	1.8				^Citation94,Citation129
Igbo			29	0		8	14–22	^Citation95,Citation130
North African			8.7	0.2				^Citation70
Kikuyu			16	0		1	33	^Citation95
Zimbabwean			13.1	0		2	34	^Citation96
South African Xhosa			13	1	19		3	^Citation75
Black Brazilian	7	3	16	0	20	10	11	^Citation97

Notes: The bold values represent allele frequencies which differ from the CPIC aggregated values for that broader ethnic category by an absolute magnitude of at least 5%. The indicator (*) is used as a standard notation for alleles of CYP450 genes.

Table 1 Number of racial and ethnic categories used for eight selected countries

Country	Number of categories used for Caucasian	Number of categories used for Asian	Number of categories used for Black
China	5	11	2
Japan	17	6	9
Malaysia	3	24	2
Russia	16	4	0
Singapore	1	14	1
South Africa	6	5	18
Sweden	4	3	9
USA	11	3	28
Total amongst all studies	66	47	62

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