Therefore, assessment in the EPM or OFT may represent a distinct aspect or trait of anxiety-like behavior depending on the test (van Gaalen and Steckler, 2000; Carola et al., 2002; Nakano et al., 2016; de Brouwer et al., 2019), which may be affected differently by the conditional clock gene knockout. The gene discussed is CLOCK; the disease is Anxiety.