Table 3.

Frequencies of CYP2C9, CYP2C19 and CYP2D6 variant alleles in the haemodialysis patients, and population reference values

CYP enzyme	Allele and activity	Allele	Allele frequency (%)
			Haemodialysis population (n = 51)		Reference populations: Caucasiansa
			n	95 % CI
CYP2C9	Normal	1a	82	74–91	78–86
	Decreased	2a	8	2–14	8–15
		3a	10	3–16	1–8
CYP2C19	Normal	1a	59	48–69	87
	Decreased	2a	21	13–28	13
		3a	0	0–3	0
	Increased	17a	20	12–27	20
CYP2D6	Normal	1a	54	45–63	33–84
	None	3a	2	0–5	0–3
		4a	21	13–28	11–29
		5a	4	0–8	1–7
		6a	2	0–5	1–2
	Decreased	9a	4	0–9	0–3
		10a	3	0–7	1–6
		41a	11	5–16	8–10b

^aData from McGraw et al. (McGraw and Waller 2012)

^bData from Preissner et al. (Sachse et al. 1997)