Skip to main content

Table 1 List of known SQTS variants and associated mutations

From: Learning from studying very rare cardiac conditions: the example of short QT syndrome

SQT subtype Gene & gene product Channel (subunit) Mutation (amino-acid change) Gain/Loss of function
SQT1 KCNH2 (hERG) IKr (α [pore-forming] sub-unit) N588K
R1135H
E50D
I560T
T618I
S631A
Gain-of-function
Gain-of-function
Gain-of-function
Gain-of-function
Gain-of-function
Gain-of-function
SQT2 KCNQ1 (KCNQ1/KvLQT1) IKs (α sub-unit) V307 L
V141 M
R259H
F279I
Gain-of-function
Gain-of-function
Gain-of-function
Gain-of-function
SQT3 KCNJ2 (Kir2.1) I K1 D172N
M301K
E299V
K346 T
Gain-of-function
Gain-of-function
Gain-of-function
Gain-of-function
SQT4 CACNA1C (CaV1.2) L-type ICa (α subunit) A39V
G490R
R1973P
R1977Q
Loss-of-function
Loss-of-function
Loss-of-function
Loss-of-function
SQT5 CACNB2b2b subunit) L-type ICa2b subunit) S481 L Loss-of-function
SQT6 CACNA2D1 L-type ICa (α2δ1 subunit) S755 T Loss-of-function
SQT7 SCN5A INa (canonical α subunit) R689H Putative loss-of-function
SQT8 SLC4A3 Anion exchanger AE3 R370H Loss-of-function
SQT9 SCN10A INa (noncanonical α subunit) G805 V Presumed loss-of-function (functional data required)
Other
Primary carnitine deficiency SLC22A5 OCTN2 W62X ♂ + R471 ♀
R471 + null
R289*
Loss-of-function
  1. Modified from [13] with additional information from [14], [18] and [85]. ♂ - inherited from father; ♀ inherited from mother; * truncation mutant