Table 3.

Multivariate analyses for MRP2 SNPs on U-Hg concentrations (µg/g creatinine).

Location/ exposure subgroup	rs1885301				rs1885301			rs717620				rs717620			rs2273697
	GGa	GA	AA	p-Value	GGa	AA + AG	p-Value	GGa	GA	AA	p-Value	GGa	AA + GA	p-Value	GGa	AA + GAb	p-Value
Indonesia
Low	p (n)	54	0.065 (47)	0.15 (5)	0.10	54	0.039 (52)	0.039	61	0.31 (42)	0.18 (8)	0.32	61	0.18 (42)	0.18	102	(2)	c
β (SE)	0.42 (0.23)	0.76 (0.52)	0.46 (0.22)	0.26 (0.25)	0.58 (0.44)	0.32 (0.24)
High	p (n)	119	0.14 (65)	0.42 (15)	0.29	119	0.12 (80)	0.12	135	0.11 (54)	0.10 (12)	0.046	135	0.40 (66)	0.40	184	0.22 (17)	0.21
β (SE)	0.34 (0.23)	0.32 (0.39)	0.34 (0.21)	0.39 (0.24)	–0.76 (0.46)	0.19 (0.23)	0.46 (0.38)
All	p (n)	190	0.075 (115)	0.19 (20)	0.12	190	0.046 (135)	0.046	213	0.11 (89)	0.52 (21)	0.18	213	0.25 (110)	0.25	306	0.20 (19)	0.20
β (SE)	0.28 (0.16)	0.40 (0.31)	0.30 (0.15)	0.27 (0.17)	–0.20 (0.31)	0.18 (0.16)	0.41 (0.32)
Philippines
Low	p (n)	71	0.11 (34)	0.59 (7)	0.20	71	0.23 (41)	0.23	76	0.13 (23)	d	0.13	76	0.13 (23)	0.13	82	0.76 (19)	0.76
β (SE)	0.33 (0.20)	–0.20 (0.38)	0.23 (0.19)	0.39 (0.25)	0.37 (0.24)	0.08 (0.25)
High	p (n)	55	0.70 (29)	0.24 (7)	0.49	55	0.45 (36)	0.45	51	0.95 (22)	0.51 (5)	0.45	51	0.86 (27)	0.86	56	0.56 (22)	0.55
β (SE)	0.11 (0.29)	0.61 (0.51)	0.21 (0.27)	–0.02 (0.33)	0.40 (0.62)	0.05 (0.31)	–0.19 (0.33)
All	p (n)	148	0.15 (78)	0.33 (16)	0.27	148	0.11 (94)	0.11	158	0.061 (49)	0.30 (9)	0.12	158	0.041 (58)	0.041	172	0.45 (46)	0.44
β (SE)	0.21 (0.15)	0.27 (0.28)	0.22 (0.14)	0.33 (0.17)	0.38 (0.36)	0.33 (0.16)	–0.13 (0.18)
Tanzania
Low	p (n)	16	0.49 (27)	0.58 (7)	0.75	16	0.44 (34)	0.44	53	(0)	(0)	c	53	(0)	c	27	0.61 (24)	0.61
β (SE)	0.21 (0.30)	0.24 (0.43)	0.22 (0.28)	0.14 (0.28)
High	p (n)	54	0.62 (63)	0.93 (19)	0.88	54	0.66 (82)	0.66	131	(2)	(1)	c	131	(3)	c	85	0.075 (46)	0.075
β (SE)	0.13 (0.26)	0.03 (0.38)	0.11 (0.25)	–0.45 (0.25)
All	p (n)	85	0.55 (101)	0.92 (32)	0.82	85	0.60 (133)	0.60	214	0.93 (5)	d	0.93	214	0.93 (5)	0.93	134	0.40 (80)	0.40
β (SE)	0.11 (0.19)	0.03 (0.26)	0.09 (0.17)	–0.05 (0.57)	–0.05 (0.57)	–0.15 (0.18)
Zimbabwe
Low	p (n)	7	0.63 (17)	0.63	7	0.63 (17)	0.63	24	(0)	(0)	c	24	(0)	c	17	0.97 (7)	0.97
β (SE)	0.32 (0.65)	0.32 (0.65)	0.02 (0.64)
High	p (n)	63	0.036 (65)	0.033 (18)	0.030	63	0.013 (83)	0.013	136	0.19 (5)	d	136	0.19 (5)	95	0.001 (46)	0.001
β (SE)	0.47 (0.23)	0.71 (0.33)	0.53 (0.21)	0.77 (0.58)	0.19	0.77 (0.58)	0.19	–0.78 (0.22)
All	p (n)	90	0.076 (103)	0.15 (22)	0.14	90	0.049 (125)	0.049	204	0.17 (6)	d	204	0.17 (6)	147	0.022 (63)	0.022
β (SE)	0.33 (0.18)	0.43 (0.30)	0.35 (0.18)	0.72 (0.53)	0.17	0.17	0.72 (0.53)	0.17	–0.44 (0.19)
Asia	p (n)	339	0.004 (194)	0.13 (36)	0.009	339	0.002 (230)	0.002	373	0.004 (138)	0.92 (30)	0.015	373	0.010 (168)	0.010	478	0.78 (65)	0.78
	β (SE)	0.33 (0.11)	0.34 (0.22)	0.33 (0.11)	0.38 (0.13)	0.03 (0.25)	0.31 (0.12)	0.05 (0.17)
Africa	p (n)	177	0.24 (206)	0.86 (55)	0.49	177	0.30 (261)	0.30	418	0.26 (11)	d	0.15	418	0.26 (11)	0.26	281	0.025 (143)	0.025
	β (SE)	0.21 (0.18)	0.05 (0.27)	0.17 (0.17)	0.59 (0.53)	0.26	0.59 (0.53)	–0.40 (0.18)
Multivariate analyses were adjusted for age, sex, and Hg storage in the “low” and “high” groups, and for age, sex, and exposure subgroup in the “All,” “Asia,” and “Africa” groups. Genotype, sex, exposure subgroup, and Hg storage were modeled as categorical (nominal) variables, and age was modeled as a continuous variable. U-HG was ln transformed. Unstandardized β-coefficients were derived from the comparison with the reference genotype, i.e., the estimated difference in ln-transformed U-Hg for two genotypes, as well as p-values and SE for these comparisons. p-Value is for the genotype term in the model. Control subgroups are not shown separately, but are included in the “All,” “Asia,” and “Africa” groups. aReference genotype. bRs2273697 AA + AG genotypes were pooled in all populations because of a low number of individuals with AA genotype. cNo analyses were run due to a low number (≤ 3) of individuals for all genotypes but one. dThe genotype was pooled with the heterozygotes due to a low number (≤ 3) of individuals.