Timothy syndrome (TS) is a rare multisystemic disorder that results from gain-of-function mutations within the CACNA1C gene, which encodes the alpha-1 subunit of voltage-dependent calcium channels.115 TS causal mutations lead to faulty inhibition of voltage-dependent channels, which results in heightened cellular excitability due to increased intracellular calcium levels.116 CACNA1C is highly expressed in the brain, lung, heart, gastrointestinal system and smooth muscle. The gene discussed is CACNA1C; the disease is Timothy syndrome.