Gene variants in CHRNA5-A3-B4, which encode for the a5, a3 and ß4 nicotinic receptor subunits, are associated with altered smoking behaviors in European Americans. Little is known about CHRNA5-A3-B4 and its association with smoking behaviors and weight in Alaska Native people, which is a population with high prevalence but low levels of tobacco consumption, extensive smokeless tobacco use and high rates of obesity. We investigated CHRNA5-A3-B4 haplotype structure and its association with nicotine intake and obesity in Alaska Native people.
A cross-sectional study of 400 Alaska Native individuals, including 290 tobacco users.
CHRNA5-A3-B4 genotype, body weight and tobacco consumption biomarkers such as plasma cotinine and urinary total nicotine equivalents (TNE).
Alaska Native people have a distinct CHRNA5-A3-B4 haplotype structure compared with European/African Americans. In 290 Alaska Native tobacco users the 'G' allele of rs578776, which tagged a 30 kb haplotype in CHRNA5-A3-B4, was prevalent (16%) and associated significantly with nicotine intake (20% higher plasma cotinine, P