Multiple distinct risk loci for nicotine dependence identified by dense coverage of the complete family of nicotinic receptor subunit (CHRN) genes.
Tobacco smoking continues to be a leading cause of preventable death. Recent research has underscored the important role of specific cholinergic nicotinic receptor subunit (CHRN) genes in risk for nicotine dependence and smoking. To detect and characterize the influence of genetic variation on vulnerability to nicotine dependence, we analyzed 226 SNPs covering the complete family of 16 CHRN genes, which encode the nicotinic acetylcholine receptor (nAChR) subunits, in a sample of 1,050 nicotine-dependent cases and 879 non-dependent controls of European descent. This expanded SNP coverage has extended and refined the findings of our previous large-scale genome-wide association and candidate gene study. After correcting for the multiple tests across this gene family, we found significant association for two distinct loci in the CHRNA5-CHRNA3-CHRNB4 gene cluster, one locus in the CHRNB3-CHRNA6 gene cluster, and a fourth, novel locus in the CHRND-CHRNG gene cluster. The two distinct loci in CHRNA5-CHRNA3-CHRNB4 are represented by the non-synonymous SNP rs16969968 in CHRNA5 and by rs578776 in CHRNA3, respectively, and joint analyses show that the associations at these two SNPs are statistically independent. Nominally significant single-SNP association was detected in CHRNA4 and CHRNB1. In summary, this is the most comprehensive study of the CHRN genes for involvement with nicotine dependence to date. Our analysis reveals significant evidence for at least four distinct loci in the nicotinic receptor subunit genes that each influence the transition from smoking to nicotine dependence and may inform the development of improved smoking cessation treatments and prevention initiatives.
Saccone
Nancy L
NL
Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110, USA. nlims@wustl.edu
Saccone
Scott F
SF
Hinrichs
Anthony L
AL
Stitzel
Jerry A
JA
Duan
Weimin
W
Pergadia
Michele L
ML
Agrawal
Arpana
A
Breslau
Naomi
N
Grucza
Richard A
RA
Hatsukami
Dorothy
D
Johnson
Eric O
EO
Madden
Pamela A F
PA
Swan
Gary E
GE
Wang
Jen C
JC
Goate
Alison M
AM
Rice
John P
JP
Bierut
Laura J
LJ
D000328:Adult; D000483:Alleles; D005260:Female; D005787:Gene Frequency / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D015810:Linkage Disequilibrium / Q000235:genetics; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011978:Receptors, Nicotinic / Q000235:genetics*; D012907:Smoking / Q000453:epidemiology / Q000235:genetics*; D014029:Tobacco Use Disorder / Q000453:epidemiology / Q000235:genetics*
D011978:Receptors, Nicotinic