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Drug addiction is a complex disorder that has been shown to have a genetic component like several other diseases. Finding any factor that is associated with higher risk of addiction tendency may influence the strategies of prevention and treatment of drug abuse and also provide an avenue of further research in genetics, immunology, and other related fields. This case-control study aimed at finding the frequency rate of ABO blood groups and Rhesus (Rh) factor among opioid dependents. Therefore, 249 opioid dependents referred to the Drug Quit center at Bam, Iran (case group) were compared with 360 blood donors referred to the Blood Transfusion Center (control group) in regard to the frequency of blood groups and Rh factor. The two groups were matched for demographic features. The odds ratio for AB blood group in addicts was 3.98 compared to non-addicts (p < .001) and the odds ratio of negative Rh in addicts compared to non-addicts was 4.27 (p < .001). According to the findings, in this population the frequency of negative Rh and AB blood group were significantly less than the predictive values. The relationship between opioid use and blood group type requires a cohort study eliminating all extraneous factors in order to be proved.
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Possible association between human blood types and opioid addiction.