Figure 1.

Schematic representation of the thalamocortical circuit and T-type Ca²⁺ channel expression. Cav3.2 and Cav3.3 channels are mainly expressed in RT (reticulothalamic) neurons; Cav3.1 channels are highly expressed in thalamocortical (TC) neurons. All three T-type calcium channels are found in different but overlapping in layers of the neocortex. Alterations in level of expression or biophysical properties of the T-type calcium channel genes (single/multiple missense mutations, alternative transcripts, epigenetic factors) in the circuit may induce pathophysiological changes in the brain with the potential to induce absence seizures.