T-type Ca²⁺ channels, largely expressed in thalamus, can induce neuronal burst firing which is critical for thalamo-cortical oscillations underlying seizures in absence epilepsy. Previous studies have shown that sequence variants of CACNA1H encoding the Ca_v3.2 channel can be associated with childhood absence epilepsy (CAE) in the Chinese population. Biophysical analysis of these variants revealed a gain-of-function for some of them compared with the wild type (WT) channel. We now identified a novel variant in CACNA1H cosegregating in a German nuclear family with CAE. It predicts substitution of serine for glycine 1158 located in the cytoplasmic loop connecting domains 2 and 3 of the channel. We used standard molecular biology and the patch clamp techniques to characterize the mutation when expressed in tsA201 cells. Our results did not show a difference between the biophysical properties of the mutant and WT channels. Since the D2-D3 loop harbours important sites for channel modulation by other proteins, further respective investigations of potential mutational effects have been initiated.