Second, Hcf1 (herein referring to Hcfc1), which is a binding partner of Ronin (Dejosez et al., 2008, 2010), was found to be part of the ataxia protein-protein interaction network (Lim et al., 2006; Zhang et al., 2020), and has been broadly implicated in neurodevelopmental disorders, including non-syndromic X-linked mental retardation (Ferrari et al., 2016; Huang et al., 2012; Vrabec et al., 2008; Turner et al., 2015; Jolly et al., 2015). The gene discussed is HCFC1; the disease is cerebellar ataxia.