In any event, a greater understanding of RhoA signaling in the nervous system is merited, given the role of RhoA in intellectual disabilities (Nadif Kasri and Van Aelst, 2008), autism spectrum disorder (Zunino et al., 2016), Alzheimer’s disease (Henderson et al., 2016; Tsushima et al., 2015), Parkinson’s disease (Labandeira-Garcia et al., 2015), and Timothy Syndrome (Krey et al., 2013), all of which exhibit altered dendritic arbors (Kulkarni and Firestein, 2012; Krey et al., 2013). The gene discussed is RHOA; the disease is Parkinson disease.