In terms of non-coding variations, a case-control study demonstrated an association between bipolar disorder and an intronic polymorphism in CAMKK2 (rs1063843; 1.9 × 10-1 minor allele frequency), where the minor allele was associated with reduced (>50%) CAMKK2 mRNA expression in human post-mortem brains and lymphoblastoid cells [39, 152]. This evidence concerns the gene CAMKK2 and bipolar disorder.