1. ¹Inserm U525, Faculté de Pharmacie, Université Henri Poincaré-Nancy1, Nancy, France
2. ²Centre de Médecine Préventive, Avenue du Doyen Parizot, Vandoeuvre-lès-Nancy, France

Correspondence: Dr S Visvikis-Siest, Inserm U525, Faculté de Pharmacie, 30 Rue Lionnois, Nancy 54000, France. Tel: +33 3 83 68 21 58; Fax: +33 3 83 32 13 22; E-mail: sophie.visvikis-siest@nancy.inserm.fr

Received 2 November 2004; Revised 11 February 2005; Accepted 16 March 2005; Published online 7 June 2005.

Abstract

This study was designed in order to investigate the influence of the genetic polymorphism of CYP2A6 on the amount of smoking. In all, 463 French adults included in the Stanislas cohort were studied and underwent two examinations at 5 years distance (t₀ and t₊₅ years). Information on their smoking habits was collected. They were genotyped by RFLP for the CYP2A6*1A, CYP2A6*1B and CYP2A6*4 alleles. CYP2A6*1B and CYP2A6*4 allele frequencies were 32 and 4%, respectively. The subjects carrying the CYP2A6*1B allele oxidize nicotine to cotinine faster than subjects with the CYP2A6*1A allele. The number of cigarettes smoked per day was significantly higher in the CYP2A6*1B/*1B group as compared to the CYP2A6*1A/*1A group (P=0.01 at t₀; P=0.001 t₊₅ years), with a larger increase in their daily cigarettes consumption over the 5-year period (P=0.006). No significant difference in the smoking status was observed according to the CYP2A6 genotype. These data suggest that the CYP2A6*1B is associated with the number of cigarettes smoked per day.