CACNA1D and Blindness: Even though there is no report on obvious visual deficiencies in animals or humans with Cav1.3 mutations, in a previous study (Busquet et al., 2010), a failure to regulate Cav1.3 is found in a mouse model of Usher syndrome, the most common cause of combined deafness and blindness in humans (Petit, 2001; Joiner and Lee, 2015).