Table 5: Genes Associated with Congenital Long QT Syndrome.
Chromosome | Gene | Ion Channel | ||
---|---|---|---|---|
LQT1 | 11 | KCNQ1, KvLQT1 | ↓IKs | 30–35 % |
LQT2 | 7 | KCNH2, HERG | ↓IKr | 20–25 % |
LQT3 | 3 | SCN5A, Nav1.5 | ↑Late INa | 5–10 % |
LQT4 | 4 | Ankyrin-B, ANK2 | ↑Cai, ↑Late INa ? | 1–2 % |
LQT5 | 21 | KCNE1, MinK | ↓IKs | 1 % |
LQT6 | 21 | KCNE2, MiRP1 | ↓IKr | Rare |
LQT7 * | 17 | KCNJ2, Kir 2.1 | ↓IK1 | Rare |
LQT8 † | 6 | CACNA1C, Cav1.2 | ↑ICa | Rare |
LQT9 | 3 | CAV3, Caveolin-3 | ↑Late INa | Rare |
LQT10 | 11 | SCN4B, NavB4 | ↑Late INa | Rare |
LQT11 | 7 | AKAP9, Yatiao | ↓IKs | Rare |
LQT12 | 20 | SNTA1, a1 Syntrophin | ↑Late INa | Rare |
LQT13 | 11 | KCNJ5, Kir 3.4 | ↓IK-ACh | Rare |
LQT14 | 14 | CALM1, Calmodulin | ↑ICa, ↑Late INa | Rare |
LQT15 | 2 | CALM2, Calmodulin | ↑ICa, ↑Late INa | Rare |
LQT16 | 19 | CALM3, Calmodulin | ↑ICa, ↑Late INa | Rare |
LQT17 | 19 | TRPM4, Transient receptor potential cation channel | ↓Inon-selctive cation channel | Rare |
*Andersen-Tawill Syndrome, † Timothy Syndrome. LQT = Long QT. Source: Modified from Obeyesekere, et al., 2015.[155]