title: CACNA1C risk variant and amygdala activity in bipolar disorder, schizophrenia and healthy controls.
abstract: OBJECTIVE
  Several genetic studies have implicated the CACNA1C SNP rs1006737 in bipolar disorder (BD) and schizophrenia (SZ) pathology. This polymorphism was recently found associated with increased amygdala activity in healthy controls and patients with BD. We performed a functional Magnetic Resonance Imaging (fMRI) study in a sample of BD and SZ cases and healthy controls to test for altered amygdala activity in carriers of the rs1006737 risk allele (AA/AG), and to investigate if there were differences across the diagnostic groups.
  
  
  METHODS
  Rs1006737 was genotyped in 250 individuals (N = 66 BD, 61 SZ and 123 healthy controls), all of Northern European origin, who underwent an fMRI negative faces matching task. Statistical tests were performed with a model correcting for sex, age, diagnostic category and medication status in the total sample, and then in each diagnostic group.
  
  
  RESULTS
  In the total sample, carriers of the risk allele had increased activation in the left amygdala. Group-wise analyses showed that this effect was significant in the BD group, but not in the other diagnostic groups. However, there was no significant interaction effect for the risk allele between BD and the other groups.
  
  
  CONCLUSIONS
  These results indicate that CACNA1C SNP rs1006737 affects amygdala activity during emotional processing across all diagnostic groups. The current findings add to the growing body of knowledge of the pleiotropic effect of this polymorphism, and further support that ion channel dysregulation is involved in the underlying mechanisms of BD and SZ.
authors: Institute of Clinical Medicine, University of Oslo, Oslo, Norway. m.s.tesli@medisin.uio.no
authors: Martin
authors: M
authors: Tesli
authors: Kristina C
authors: KC
authors: Skatun
authors: Olga Therese
authors: OT
authors: Ousdal
authors: Andrew Anand
authors: AA
authors: Brown
authors: Christian
authors: C
authors: Thoresen
authors: Ingrid
authors: I
authors: Agartz
authors: Ingrid
authors: I
authors: Melle
authors: Srdjan
authors: S
authors: Djurovic
authors: Jimmy
authors: J
authors: Jensen
authors: Ole A
authors: OA
authors: Andreassen
mesh_terms: D000483:Alleles; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology*; D001714:Bipolar Disorder / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*; D020746:Calcium Channels, L-Type / Q000235:genetics*; D006801:Humans; D008279:Magnetic Resonance Imaging; D020641:Polymorphism, Single Nucleotide; D011597:Psychomotor Performance; D011930:Reaction Time; D012559:Schizophrenia / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology*
chemical_list: C079146:CACNA1C protein, human; D020746:Calcium Channels, L-Type