Monoamine oxidase polymorphisms and smoking behaviour in Japanese

Abstract

Although nicotine dependence is one of the primary reasons why smokers cannot quit smoking, nicotine cannot explain all of the psychopharmacological effects of tobacco smoke. Accumulating evidence points to potent inhibition of monoamine oxidase (MAO) which metabolizes neurotransmitters relating to additive behaviour. We have therefore investigated the association between smoking behaviour and MAO ( variable number of tandem repeat in the promoter region and A644G) polymorphisms. The genotypes were examined in 504 Japanese outpatients (217 men and 287 women) who visited Aichi Cancer Centre Hospital. The age-adjusted odds ratios (aORs) were estimated by a logistic model. Among males, we did not find a significant association of the smoking habit with either of the polymorphisms. The median Fargastrom test for nicotine dependence (FTND) score among male current smokers was significantly higher with than without the 4-repeat allele (5.8 and 4.7, respectively). The aOR of FTND 6 versus FTND 6 was 2.72 (95% confidence interval 1.13-6.50) for males with the 4-repeat allele. Among females, the aOR of being current smokers compared to never smokers was 0.49 (0.26-0.93) for individuals with the 4-repeat allele. Our results indicate that the polymorphisms of influence the smoking habit for female, as well as the nicotine dependence and smoking initiation for male smokers. These findings among male smokers support the view that MAO affects a smokers' requirement for nicotine and may explain why some people are predisposed to tobacco addiction and why some individuals find it difficult to stop smoking.

Association between neuropeptide Y receptor 2 polymorphism and the smoking behavior of elderly Japanese

“…These values are slightly lower than in a recent report 20 stating that the prevalence of male and female Japanese current smokers 60 years of age or more is 27.8 and 6.2%, respectively. The mean CPD values, FTND scores and TDS scores in this study were lower than those previously reported in Japanese 19,21 or American smokers 22 (Table 1). The CPD values of male ex-smokers were higher than those of male current smokers, and TDS scores of the current smokers of both sexes were higher than the TDS scores of ex-smokers of both sexes.…”

Overview of the pharmacogenomics of cigarette smoking

“…105 Although the four-repeat allele did not influence smoking status (current, former, never), it was associated with higher levels of ND in Japanese males. 106 Conversely, Japanese women with the four-repeat allele had a reduced risk of being a current smoker, although no association to ND was found. 106 Another study of Chinese males found those with both the four-repeat allele and 1460C allele were least likely to be current smokers.…”

“…106 Conversely, Japanese women with the four-repeat allele had a reduced risk of being a current smoker, although no association to ND was found. 106 Another study of Chinese males found those with both the four-repeat allele and 1460C allele were least likely to be current smokers. 107 In adolescents, no associations of the MAO-A VNTR polymorphisms or 1460C4T SNP were found between current, former or never smokers.…”

Significant association of interleukin 8 −251T/A polymorphism with smoking behavior in a Japanese population

“…Regarding the potential for genetic predisposition to habitual smoking, polymorphisms have hitherto been investigated with genes for neurotransmitters and fac-tors in nicotine metabolism such as the dopamine receptors DRD2 (Hamajima et al 2002;Noble et al 1994;Spitz et al 1998;Yoshida et al 2001) and DRD4 (Hutchison et al 2002;Shields et al 1998), a dopamine transporter (SLC6A3) (Lerman et al 1999;Sabol et al 1999) and a serotonin transporter (5-HTT) (Ishikawa et al 1999), as well as dopamine metabolism-related genes (MAO) (Ito et al 2003;Johnstone et al 2002;McKinney et al 2000) and cytochrome p450 2A6 (CYP2A6) (Pianezza et al 1998). Taking the present results into account, one may hypothesize that smoking behavior is influenced not only by neuropsychological but also by inflammatory factors.…”