To determine the meditatory effect of circadian rhythms in mood disorders, the authors performed a study involving 444 Canadian and American families. 198 SNPs were assessed for relationships with bipolar disorder and chronotype preferences (as measured by a questionnaire for major depression, bipolar disorder, and psychosis and the Basic Language Morningness Scale respectively).
The results indicated that a C/T SNP in the rev-erb-α gene (rs2314339) is associated with bipolar disorder. Additionally, the per3 SNP rs228697 was found to be associated with eveningness and a csnk1e SNP with morning preference.
rs2314339 in rev-erb-α
rs228697 in per3