Background: Fatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGLL) are the major endocannabinoid metabolic enzymes. Owing to the importance of endocannabinoid system in addiction, the Pro129Thr polymorphism in the FAAH gene has reportedly been associated with substance abuse and dependence in a Caucasian population.
Objective: To determine whether the single nucleodtide polymorphisms of the FAAH and MGLL genes are associated with alcoholism in a Japanese population.
Methods: We conducted case–control studies for total 14 tag single nucleotide polymorphisms in those two genes using Japanese 729 patients with alcoholism and 799 healthy controls. Genotype and allele frequencies were compared between these groups.
Results: None of these genetic markers, however, showed significant association with alcoholism in Japanese.
Conclusion: Whereas we examined associations in a larger sample size between alcoholism and tag single nucleotide polymorphisms that covered most regions of these endocannabinoid metabolic enzyme genes, we found that these are not associated with susceptibility to alcoholism in a Japanese population.
aDepartment of Medical Genetics, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki
bNational Alcoholism Center, Kurihama National Hospital, Yokosuka, Kanagawa, Japan
cDepartment of Biology, William Paterson University, Wayne, NJ, USA
Correspondence to Dr Hiroki Ishiguro, MD, PhD, Department of Medical Genetics, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8577, Japan
Tel: +81 29 853 3352; fax: +81 29 853 3333;
Received 9 January 2006 Accepted 8 January 2007