In bipolar disorder, one commonly identified endophenotype is a deficit in face emotion labeling, which is found in both individuals with bipolar disorder and in individuals who are "at risk" (i.e., have a first degree relative with bipolar disorder).  Using fMRI, this endophenotype has been linked to dysfunction in the dorsolateral and ventrolateral prefrontal cortex, anterior cingulate cortex, striatum, and amygdala. A polymorphism in the CACNA1C gene coding for the voltage-dependent calcium channel Ca1.2 has been found to be associated with deficits in facial emotion recognition.