title: Examination of the nicotine dependence (NICSNP) consortium findings in the Iowa adoption studies population.
abstract: BACKGROUND
  Nicotine dependence results from a complex interplay of genetic and environmental factors. Over the past several years, a large number of studies have been performed to identify distinct gene loci containing genetic vulnerability to nicotine dependence. Two of the most prominent studies were conducted by the Collaborative Study of the Genetics of Nicotine Dependence (NICSNP) Consortium using both candidate gene and high-density association approaches.
  
  
  METHODS
  We attempted to confirm and extend the most significant findings from the high-density association study and the candidate gene study using the behavioral and genetic resources of the Iowa Adoption Studies, the largest case-control adoption study of substance use in the United States.
  
  
  RESULTS
  We found evidence that genetic variation at CHRNA1, CHRNA2, CHRNA7, and CHRNB1 alters susceptibility to nicotine dependence, but we did not replicate any of the most significant single nucleotide polymorphism associations from the NICSNP high-density association study.
  
  
  CONCLUSIONS
  Further examination of the NICSNP findings in other population samples is indicated.
authors.affiliation: Department of Psychiatry and Neuroscience and Genetics Programs, University of Iowa, Rm 2-126 MEB, Iowa City, IA 52242, USA. robert-philibert@uiowa.edu
authors.forename: Robert A
authors.initials: RA
authors.lastname: Philibert
authors.forename: Alexandre
authors.initials: A
authors.lastname: Todorov
authors.forename: Allan
authors.initials: A
authors.lastname: Andersen
authors.forename: Nancy
authors.initials: N
authors.lastname: Hollenbeck
authors.forename: Tracy
authors.initials: T
authors.lastname: Gunter
authors.forename: Andrew
authors.initials: A
authors.lastname: Heath
authors.forename: Pamela
authors.initials: P
authors.lastname: Madden
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007484:Iowa; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D020033:Protein Isoforms / Q000235:genetics; D011978:Receptors, Nicotinic / Q000235:genetics; D012044:Regression Analysis; D014029:Tobacco Use Disorder / Q000235:genetics*
chemical_list: D020033:Protein Isoforms; D011978:Receptors, Nicotinic