Another genetic mutation that has received a great deal of attention occurs in the gene Disrupted-in-Schizophrenia 1 (DISC1) and was found to co-segregate with psychiatric illness including schizophrenia, bipolar disorder and depression in a large Scottish family (St Clair et al., 1990; Millar et al., 2000). The gene discussed is DISC1; the disease is schizophrenia.