CDH13 and attention deficit-hyperactivity disorder: The era of genome-wide association studies (GWAS) has brought further evidence of pleiotropic effects attributed to CDH13. Genetic risk variants in CDH13 have been identified for cancer (Thomas et al. 2008) and neuropsychiatric disorders such as attention-deficit/hyperactivity disorder (ADHD), autism and dependence on psychotic substances (Rivero et al. 2013; Redies et al. 2012).