title: No association of candidate genes with cannabis use in a large sample of Australian twin families.
abstract: While there is solid evidence that cannabis use is heritable, attempts to identify genetic influences at the molecular level have yielded mixed results. Here, a large twin family sample (n = 7452) was used to test for association between 10 previously reported candidate genes and lifetime frequency of cannabis use using a gene-based association test. None of the candidate genes reached even nominal significance (P < 0.05). The lack of replication may point to our limited understanding of the neurobiology of cannabis involvement and also to potential publication bias and false-positive findings in previous studies.
authors.affiliation: Queensland Statistical Genetics Laboratories, Queensland Institute of Medical Research, Brisbane, Australia. karin.verweij@qimr.edu.au
authors.forename: Karin J H
authors.initials: KJ
authors.lastname: Verweij
authors.forename: Brendan P
authors.initials: BP
authors.lastname: Zietsch
authors.forename: Jimmy Z
authors.initials: JZ
authors.lastname: Liu
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Medland
authors.forename: Michael T
authors.initials: MT
authors.lastname: Lynskey
authors.forename: Pamela A F
authors.initials: PA
authors.lastname: Madden
authors.forename: Arpana
authors.initials: A
authors.lastname: Agrawal
authors.forename: Grant W
authors.initials: GW
authors.lastname: Montgomery
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Heath
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Martin
mesh_terms: D000328:Adult; D001315:Australia; D005260:Female; D005796:Genes / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000235:genetics; D055106:Genome-Wide Association Study; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000235:genetics*; D008875:Middle Aged; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*