Table 2.

Human association studies of the Cannabinoid receptor 1 (CNR1) gene

Authors (Date)	Phenotype	Significant Polymorphism	Summary
*Comings [43]	Alcohol, cocaine, cannabis, amphetamine, intravenous drug abuse	AAT repeat	5+ repeats associated with drug dependence
Li [41]	Heroin abuse	AAT repeat	No association in this Chinese population
Heller [42]	Intravenous drug addiction	AAT repeat	No association
		1359G/A
Covault [40]	Drug dependence	AAT repeat	No association
Schmidt [157]	Severe alcohol dependence	1359G/A	A/A genotype associated with a history of alcohol delirium
Zhang [36]	Polysubstance abuse	rs2023239	TAG haplotype strongly associated with polysubstance abuse; TAG is associated with reduced mRNA expression in cerebral cortex and midbrain
		rs806379
		rs1535255
		−3180T indel
Ballon [44]	Cocaine dependence with and without schizophrenia	AAT repeat	AAT (12) repeat was higher in cocaine dependent cases, particularly those with schizophrenia, compared to controls in this African-Carribean sample
*Herman [39]	Cannabis, cocaine, opioid, alcohol and polysubstance dependence	rs1535255	Modest association with alcohol dependence (no comorbid drug dependence)
*Hopfer [37]	Cannabis dependence symptoms	rs806380	Rs806380 & haplotypes of rs6454674-rss806380-rs806377-rs1049353 (GGCC, TACC, GACC) associated with cannabis problems
Zuo [47]	Alcohol dependence, drug dependence, comorbid	rs6454674	Interaction between rs6454674 (G/G or G/T) and rs806368 (T/T) influence alcohol and drug dependence
		rs806368
Chen [46]	Smoking initiation, Nicotine	rs2023239	Single SNP and haplotype effects on nicotine dependence in women
	Dependence	rs12720071
		rs806368
Hutchison [48]	CB1 receptor density in postmortem brain, Imaging outcomes; Rewarding effects of alcohol	rs2023239	Individuals with the CT genotype report greater CB1 binding, greater activation of mesocorticolimbic activation and greater reward and positive affect after drinking
*Haughey [45]	Marijuana Dependency Checklist	rs2023239	Individuals with CT genotype report higher dependency scores, smoke greater quantities and more often and also report heavier alcohol use.
	Marijuana Withdrawal Checklist
	Profile of Mood States (POMS)		CT Individuals also indicate greater craving at abstinence, post-abstinence and post cue exposure.
	Craving and Mood Questionnaire
	Alcohol consumption
*Agrawal [38]	Cannabis dependence	rs806380,	Associated with DSM-IIIR cannabis dependence in alcoholic families
		rs806368,
		rs806379

^*Studied cannabis dependence specifically.