T-type, low-voltage activated, calcium channels, now designated Cav3 channels, are involved in a wide variety of physiological functions, especially in nervous systems. Their unique electrophysiological properties allow them to finely regulate neuronal excitability and to contribute to sensory processing, sleep, and hormone and neurotransmitter release. In the last two decades, genetic studies, including exploration of knock-out mouse models, have greatly contributed to elucidate the role of Cav3 channels in normal physiology, their regulation, and their implication in diseases. Mutations in genes encoding Cav3 channels (CACNA1G, CACNA1H, and CACNA1I) have been linked to a variety of neurodevelopmental, neurological, and psychiatric diseases designated here as neuronal Cav3 channelopathies. In this review, we describe and discuss the clinical findings and supporting in vitro and in vivo studies of the mutant channels, with a focus on de novo, gain-of-function missense mutations recently discovered in CACNA1G and CACNA1H. Overall, the studies of the Cav3 channelopathies help deciphering the pathogenic mechanisms of corresponding diseases and better delineate the properties and physiological roles Cav3 channels.

T型低压激活的钙通道（现称为Cav3通道）涉及多种生理功能，尤其是在神经系统中。它们独特的电生理特性使它们能够很好地调节神经元的兴奋性，并有助于感觉处理，睡眠以及激素和神经递质的释放。在过去的二十年中，基因研究（包括敲除小鼠模型的探索）为阐明Cav3通道在正常生理中的作用，其调控及其在疾病中的意义做出了巨大贡献。编码Cav3通道的基因（CACNA1G，CACNA1H和CACNA1I的突变）与多种神经发育，神经和精神疾病相关，此处称为神经元Cav3通道病。在这篇综述中，我们描述和讨论了突变通道的临床发现以及对体内和体外研究的支持，重点是最近在CACNA1G和CACNA1H中发现的从头获得，功能获得的错义突变。总体而言，对Cav3通道病的研究有助于破译相应疾病的致病机制，并更好地描述Cav3通道的特性和生理作用。