RAI1 and Anxiety: 54) graded overexpression of Rai1, finding that animals with 1.5- to 2-fold Rai1 overexpression showed PTLS-like features, such as growth retardation, reduced body weight, increased anxiety-like behaviours and heightened locomotor activity. Additionally, in Rai1 conditionally transgenic mice with Rai1 specifically overexpressed in the hippocampus, cerebral cortex, striatum, amygdala and olfactory bulb, significant weight loss was also observed (Ref. 56).