Previous studies testing the role of Htr1a hetero-receptors on anxiety either used expression of Htr1a under control of the Camk2a promoter on an otherwise knockout background (Gross et al., 2002) or used the suppression of endogenous Htr1a in Camk2a-expressing cells (Richardson-Jones et al., 2011). This evidence concerns the gene CAMK2A and Anxiety.