Immunophenotypes associated with bipolar disorder and lithium treatment.

Immune dysfunction is implicated in the etiology of bipolar disorder. The single-nucleotide polymorphism rs17026688 in the gene encoding glutamate decarboxylase-like protein 1 (GADL1) has been found to be associated with lithium response in Han Chinese patients with bipolar I disorder (BDI). However, whether patients with GADL1 polymorphisms have different immunophenotypes is unknown.

Lithium and GADL1 regulate glycogen synthase kinase-3 activity to modulate KCTD12 expression.

Potassium channel tetramerization domain containing 12 (KCTD12), the auxiliary GABA receptor subunit, is identified as a susceptibility gene for bipolar I (BPI) disorder in the Han Chinese population. Moreover, the single-nucleotide polymorphism (SNP) rs17026688 in glutamate decarboxylase-like protein 1 (GADL1) is shown to be associated with lithium response in Han Chinese BPI patients. In this study, we demonstrated for the first time the relationship among lithium, GADL1, and KCTD12.