SLC6A13 and fragile X syndrome: Moreover, a number of the genes we found to be significantly altered in the BTBR mouse, while not directly linked to ASD, have been implicated in diseases with a similar trajectory: TSC2 (tuberous sclerosis; Persico and Bourgeron, 2006), PAK1 (FXS; Hayashi et al., 2007), Nr4a2 (Parkinson's, schizophrenia, and manic depression; Lybaek et al., 2009), intellectual disability (Smith et al., 2005), Alzheimer's disease (Pardo and van Duijn, 2005), Slc6a13 (anxiety disorders; Saus et al., 2010), and Adra2c (ADHD; Cho et al., 2008).