title: Lack of association of EGR2 variants with bipolar disorder in Japanese population.
abstract: The early growth response gene 2 (EGR2) has been recently reported to be associated with bipolar disorder in the Korean population. However replication studies in independent cohorts of same and different ethnicities are essential for establishing the credibility of a genotype-phenotype association. With this notion, in the present study we have performed a replication study of the reported association of SNPs in EGR2 in a case-control study comprising of 867 unrelated Japanese bipolar disorder patients and 895 age-, sex- and ethnicity-matched controls. Results showed no significant differences in allele and genotype frequencies of EGR2 SNPs between bipolar disorder patients and controls and also in a sex-stratified genetic analysis. The haplotype and meta-analyses also showed no significant association with bipolar disorder. In conclusion, this is the first replication study of the previously reported association of EGR2 with bipolar disorder in a larger sample set and the results showed that the EGR2 gene is unlikely to contribute to the susceptibility of bipolar disorder in a Japanese cohort.
authors.affiliation: Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Saitama 351-0198, Japan.
authors.forename: Shabeesh
authors.initials: S
authors.lastname: Balan
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamada
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Iwayama
authors.forename: Tomoko
authors.initials: T
authors.lastname: Toyota
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Motoko
authors.initials: M
authors.lastname: Maekawa
authors.forename: Manabu
authors.initials: M
authors.lastname: Toyoshima
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Iwata
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Suzuki
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ujike
authors.forename: Toshiya
authors.initials: T
authors.lastname: Inada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kunugi
authors.forename: Norio
authors.initials: N
authors.lastname: Ozaki
authors.forename: Nakao
authors.initials: N
authors.lastname: Iwata
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Nanko
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Kato
authors.forename: Takeo
authors.initials: T
authors.lastname: Yoshikawa
mesh_terms: D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001714:Bipolar Disorder / Q000235:genetics*; D016022:Case-Control Studies; D051767:Early Growth Response Protein 2 / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D007564:Japan; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide
chemical_list: D051767:Early Growth Response Protein 2
keywords: Bipolar disorder; COSMO; Collaborative Study of Mood Disorders consortium; DSM-IV; Diagnostic and Statistical Manual of Mental Disorders-IV; EGR2; Early growth response gene; Genetic association; LD; Replication study; SNP; early growth response gene 2; linkage disequilibrium; single nucleotide polymorphism