KIRREL3 and attention deficit-hyperactivity disorder: Knockout of the Kirrel3 gene in mice led to auditory sensory and motor skill impairment and ADHD (attention deficit and hyperactivity disorder) (Hisaoka et al., 2018), as well as an increased risk of ADHD in children following prenatal METH exposure (Pendergast et al., 2012; Petzold et al., 2021).