Table 3.

The most significant associations of single SNPs with heroin addiction

a.
SNP	Gene	Allele test			Genotype testa		Effect of the minor allele
		P - Value		OR (95% CI)	P- Value
		US only	Combined	Combined	US only	Combined
Group 1
rs510769	OPRM1	0.0003	0.0008	1.7 (1.2–2.2)	0.001	0.0029	risk
rs3778151	OPRM1	0.0007	0.003	1.7 (1.2–2.4)	0.003	0.015	risk
rs6473797	OPRK1	0.0009	0.004	0.7 (0.5–0.9)	0.003	0.011	protection
rs1534891	CSNK1E	0.0016	0.002	0.6 (0.4–0.8)	0.002	0.001	protection
rs694066	GAL	0.0019	0.001	2.1 (1.3–3.6)	0.006	0.004	risk
rs2236861	OPRD1	0.0029	0.002	1.6 (1.7–2.2)	0.003	0.003	risk
Group 2
rs3766951	OPRD1	0.0125	0.009	1.4 (1.1–1.9)	0.040	0.030	risk
rs2236857	OPRD1	0.0165	0.008	1.5 (1.1–1.9)	0.019	0.005	risk
rs3758987	HTR3B	0.0174	0.007	1.5 (1.1–2.0)	0.049	0.019	risk

b. SNP location
SNP	Gene Symbol	Gene	Gene Location	Chr.	Position Build 36.2
rs510769	OPRM1	mu opioid receptor	intron 1	6	154403712
rs3778151	OPRM1	mu opioid receptor	intron 1	6	154435373
rs6473797	OPRK1	kappa opioid receptor	intron 2	8	54315535
rs1534891	CSNK1E	casein kinase 1, epsilon	intron 7	22	37025045
rs694066	GAL	galanin	intron 2	11	68209561
rs2236861	OPRD1	delta opioid receptor	intron 1	1	29012343
rs2236857	OPRD1	delta opioid receptor	intron 1	1	29034196
rs3766951	OPRD1	delta opioid receptor	intron 1	1	29042146
rs3758987	HTR3B	serotonin receptor 3B	−381	11	113280485

^aadditive mode of inheritance.