. 2013 May 10;121(7):797–803. doi: 10.1289/ehp.1206003

Table 4.

Multivariable regression analyses^a of the influence of N6AMT1 haplotypes on fractions of arsenic metabolites.

Metabolite/N6AMT1 haplotype (sequence)	n	Copy nr^b	Mean (95%CI)^c	Model 1		Model 2
Metabolite/N6AMT1 haplotype (sequence)	n	Copy nr^b	Mean (95%CI)^c	β (95%CI)	p-Value	β (95%CI)	p-Value
iAs
Haplotype 1 (AATG)	30	2	13.8 (11.7, 16.0)
	81	1	12.5 (11.2, 13.8)	–1.3 (–3.9, 1.2)	0.30	–1.2 (–3.7, 1.3)	0.34
	77	0	12.5 (11.1, 13.9)	–1.3 (–3.9, 1.2)	0.30	–1.7 (–4.2, 0.79)	0.18
Haplotype 3 (ATTG)	5	2	16.2 (11.0, 21.6)
	46	1	11.7 (10.0, 13.5)	–4.6 (–10, 0.96)	0.10	–4.4 (–9.8, 1.1)	0.18
	137	0	12.9 (11.9, 13.9)	–3.4 (–8.8, 2.0)	0.21	–3.5 (–8.8, 1.8)	0.19
Haplotype 9 (GTGT)	72	0	12.7 (11.4, 14.2)
	73	1	13.0 (11.6, 14.4)	0.97 (–1.4, 3.3)	0.79	0.020 (–1.9, 2.0)	0.98
	43	2	12.1 (10.3, 13.9)	0.69 (–1.4, 3.3)	0.55	–1.3 (–3.5, 0.98)	0.27
MMA
Haplotype 1 (AATG)	30	2	7.2 (6.0, 8.3)
	81	1	8.6 (7.8, 9.2)	1.3 (–0.70, 2.7)	0.063	1.3 (0.058, 2.6)	0.041
	77	0	9.2 (8.6, 10.0)	2.1 (0.75, 3.5)	0.003	1.8 (0.55, 3.1)	0.005
Haplotype 3 (ATTG)	5	2	6.9 (4.3, 10.2)
	46	1	8.4 (7.4, 9.3)	1.1 (–1.9, 4.2)	0.48	1.4 (–1.5, 4.2)	0.35
	137	0	8.7 (8.2, 9.3)	1.5 (–1.5, 4.5)	0.33	1.4 (–1.4, 4.2)	0.32
Haplotype 9 (GTGT)	72	0	7.8 (7.1, 8.6)
	73	1	8.9 (8.0, 9.5)	0.90 (–0.17, 2.0)	0.098	0.64 (–0.37, 1.6)	0.21
	43	2	9.6 (8.8, 10.7)	1.9 (0.72, 3.2)	0.002	1.5 (0.35, 2.7)	0.011
DMA
Haplotype 1 (AATG)	30	2	79.0 (76.4, 81.6)
	81	1	79.0 (77.5, 80.7)	0.032 (–3.0, 3.1)	0.98	–0.14 (–3.0, 2.8)	0.92
	77	0	78.3 (76.6, 79.8)	–0.81 (–3.9, 2.3)	0.60	–0.16 (–3.1, 2.8)	0.92
Haplotype 3 (ATTG)	5	2	77.0 (77.2, 79.6)
	46	1	79.9 (77.8, 82.0)	3.4 (–3.3, 10)	0.32	3.0 (–3.4, 9.3)	0.36
	137	0	78.4 (77.2, 79.6)	1.9 (–4.6, 8.5)	0.57	2.1 (–4.1, 8.2)	0.51
Haplotype 9 (GTGT)	72	0	79.5 (77.8, 81.1)
	73	1	78.3 (76.6, 80.0)	–1.2 (–2.7, 2.9)	0.34	–0.66 (–2.9, 1.6)	0.57
	43	2	78.1 (76.0, 80.4)	–1.3 (–1.5, 4.0)	0.37	–0.25 (–2.9, 2.4)	0.85
^aModel 1: Arsenic metabolite (%iAs or %DMA or %MMA)=α+β×N6AMT1 haplotype+γ×U-As (ln transformed). Model2: Arsenic metabolite=α+β×N6AMT1 haplotype+γ×U-As (ln)+λ×AS3MT haplotype2. ^bNumber of copies of each haplotype associated with lower %MMA are denoted first. ^cMean values and 95% CIs are adjusted values based on model1.