The ability of plasma cotinine to predict nicotine and carcinogen exposure is altered by differences in CYP2A6: the influence of genetics, race, and sex.

ABSTRACT:

Background

Cotinine, a nicotine metabolite, is a biomarker of tobacco, nicotine, and carcinogen exposure. However, a given cotinine level may not represent the same tobacco exposure; for example, African-Americans have higher cotinine levels than Caucasians after controlling for exposure.

Methods

Cotinine levels are determined by the amount of cotinine formation and the rate of cotinine removal, which are both mediated by the enzyme CYP2A6. Because CYP2A6 activity differs by sex (estrogen induces CYP2A6) and genotype, their effect on cotinine formation and removal was measured in nonsmoking Caucasians (Study 1, n = 181) infused with labeled nicotine and cotinine. The findings were then extended to ad libitum smokers (Study 2, n = 163).

Results

Study 1: Reduced CYP2A6

SUBMITTER: Zhu AZ 

PROVIDER: S-EPMC3617060 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature