JPBS

Bipolar disorder is an affective disorder with mood swings between the pole of depression and the pole of mania. The mechanism of those mood swings has not been completely elucidated yet. According to current scientific knowledge affective episodes are caused by a concatenation between a genetic predisposition and biopsychosocial triggers. Even though diverse genome wide associated gene variants (e.g., single nucleotide polymorphisms of CACNA1C, ANK3 or NCAN) were associated with Bipolar disorder in the last decade, there is still missing heritability. Thus, innovative approaches and endophenotypes of Bipolar disorder must be used to decipher the underlying disease mechanisms of Bipolar disorder. Recently, the Polygenic Risk Score for Schizophrenia was investigated in the lithium response endophenotype of Bipolar disorder. The polygenic score for Schizophrenia was inversely associated with the lithium response phenotype in study participants with Bipolar disorder. Furthermore, there are genetic overlaps between psychiatric diseases, which also demonstrates the importance of cross-disorder design studies to elucidate the missing heritability of Bipolar disorder.

bipolar disorder; polygenic risk score; schizophrenia