TCF7L2 and Intellectual disability: Notably, the genes encoding for β-catenin (CTNNB1) and the TCF4/TCF7L2 transcription factor have been consistently associated with ASD and intellectual disability in several large-scale sequencing studies (de Ligt et al., 2012; O’Roak et al., 2012a, b; De Rubeis et al., 2014; Iossifov et al., 2014; Deciphering Developmental Disorders Study, 2015; Lelieveld et al., 2016; Marchetto et al., 2017; Satterstrom et al., 2020; Wang T. et al., 2020).