Study of 45 candidate genes suggests CACNG2 may be associated with lithium response in bipolar disorder

J Affect Disord. 2019 Apr 1;248:175-179. doi: 10.1016/j.jad.2019.01.010. Epub 2019 Jan 15.


Background: Bipolar disorder is a neuropsychiatric disorder that is characterized by fluctuations between manic and depressive phases. Lithium is the original and best mood stabilizing treatment for bipolar disorder. While its mechanism is not well understood, it is believed to have a strong genetic component, as several studies suggest that lithium responsiveness, in bipolar disorder, is heritable. In this study we aimed to identify genetic variants that are associated with lithium responsiveness in bipolar disorder.

Methods: Here we present two cohorts; a retrospective cohort in which patients were surveyed about their response to lithium, and a prospective cohort, in which patients were placed on a lithium monotherapy and monitored for their response to lithium. In both cohorts, patients were stratified into two categories in terms of lithium response; good responders and poor responders. 45 genes were selected based on previous associations with lithium pathways or bipolar disorder and 684 SNPs within these genes were selected to test for association with lithium response.

Results: While no single SNP was significant after correcting for multiple comparisons, there were several that were nominally significant (p < 0.05). Of these nominally significant SNPs, the most highly significant SNP in both the prospective and retrospective cohorts were found to be in CACNG2, or Stargazin. The second best association with lithium response was several SNPs in NRG1, a gene that has previously been associated with schizophrenia.

Conclusions: Evidence for the association of lithium response with SNPs in CACNG2 is consistent with previous findings that have identified CACNG2 as associated with both bipolar disorder and lithium responsiveness.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antimanic Agents / pharmacokinetics*
  • Bipolar Disorder / drug therapy*
  • Bipolar Disorder / genetics*
  • Calcium Channels / drug effects*
  • Female
  • Humans
  • Lithium Compounds / pharmacokinetics*
  • Male
  • Middle Aged
  • Pharmacogenomic Variants
  • Polymorphism, Single Nucleotide
  • Prospective Studies
  • Retrospective Studies
  • Young Adult


  • Antimanic Agents
  • CACNG2 protein, human
  • Calcium Channels
  • Lithium Compounds