Association studies of dopamine synthesis and metabolism genes with multiple phenotypes of heroin dependence

BMC Medical Genetics

Table 3 The associations between SNPs and age of onset for heroin use

Gene	Variable/ID	Age ≤ 28 (n = 440)		Age > 28 (n = 361)		P^a	OR, 95% CI	P^b	Exp(B), 95% CI
		Number	Percent	Number	Percent
TH	rs10770140					0.018ⁿ		0.092
	TT	366	83.2	322	89.2	0.015ⁿ	0.599, 0.395–0.908	0.019ⁿ	0.568, 0.354–0.912
	TC	72	16.4	39	10.8	0.023	1.615, 1.064–2.452	0.032	1.681, 1.047–2.703
	CC	2	0.5	0	0.0	0.504	1.005, 0.998–1.011	0.999	0.000, 0.000-
	T	804	91.4	683	94.6	0.013ⁿ	0.604, 0.405–0.901
	C	76	8.6	39	5.4
	rs10770141					0.015ⁿ		0.071
	GG	371	84.3	326	90.3	0.012ⁿ	0.577, 0.374–0.890	0.014ⁿ	0.538, 0.328–0.881
	GA	67	15.2	35	9.7	0.019	1.673, 1.083–2.585	0.024	1.77, 1.080–2.907
	AA	2	0.5	0	0.0	0.504	1.005, 0.998–1.001	0.999	0.000, 0.000-
	G	809	91.9	687	95.2	0.010ⁿ	0.580, 0.382–0.881
	A	71	8.1	35	4.8

P^a: Genotypic and allele frequency difference assessment by chi-square test
P^b: Genotypic and allele frequency difference assessment by binary logistic regression
ⁿ: The result was not significant after Bonferroni’s correction

ISSN: 1471-2350