SCN3B

SCN3B is a gene that encodes a subunit of the voltage-gated sodium channel in humans. This gene is located on the short arm of chromosome 11 (11q23.3). The protein encoded by this gene is a beta subunit, which is part of the ion channel that produces the sodium ion current in cardiac myocytes.

Function

The SCN3B gene encodes the beta-3 subunit of the voltage-gated sodium channel. This subunit is not responsible for the channel's voltage-dependent activation, but it modulates the kinetics of channel inactivation and plays a role in channel assembly. The beta-3 subunit also interacts with the alpha subunit to increase the cell surface expression of the channel and to affect the channel's gating characteristics.

Clinical significance

Mutations in the SCN3B gene have been associated with Brugada syndrome, a genetic disorder that can cause life-threatening irregular heart rhythms. In addition, these mutations can also cause cardiac conduction disease, which can lead to heart block, a condition where the electrical signals in the heart are delayed or blocked.

See also

• Sodium channel
• Brugada syndrome
• Cardiac conduction disease