Taken together, the current findings in 5-HT1A receptor KO mice do not support a role of these receptors in Meth-induced psychosis, although this does not rule out a role of other serotonin receptors, which can be addressed in future studies with selected KO lines such as 5-HT1B and 5-HT2 receptor KO mice. This evidence concerns the gene HTR1A and psychotic disorder.