In two rodent studies, one with 5HT2A knockout mice (Weisstaub et al., 2006) and the other in rats with anti-sense-mediated 5HT2A downregulation (Cohen, 2005), the rodents displayed decreased anxiety-like behavior and in the trial with the 5HT2A knockout mice (Weisstaub et al., 2006), restoration of 5HT2A receptors in the pre-frontal cortex (PFC) re-established anxiety-like behaviors. The gene discussed is HTR2A; the disease is Anxiety.