In 2004, Splawski et al. [41] could specify the phenotypic characterization of the Timothy syndrome and finally attribute its variegated clinical attributes to a de novo missense mutation in the CaV1.2 L-type calcium channel gene: Analysis of the affected patients CaV1.2 splice variant revealed a G121A transition in exon 8A. This evidence concerns the gene CACNA1C and Timothy syndrome.