SCN5A Variant G1548K

Summary of observed carriers, functional annotations, and structural context for SCN5A G1548K. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT3 penetrance

4%

0/13 effective observations

Estimated BrS1 penetrance

54%

7/13 effective observations

Total carriers

3

3 BrS1 · 0 LQT3 · 0 unaffected

G1548K has not been reported in gnomAD. This residue resides in a Hotspot region for Brugada syndrome and a Non_Hotspot region for LQT3.

Variant features alone are equivalent to phenotyping 4 individuals for Brugada syndrome and 0 individuals for LQT3.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA 2.97 None 64 2

PROVEAN scores below -2 suggest deleterious impact. REVEL scores above 0.5–0.75 are often interpreted as likely pathogenic. PolyPhen-2 scores above 0.85 are typically pathogenic. Penetrance density summarises neighbouring residue risk (Kroncke et al. 2019).

Reported carrier data

Observed carriers by publication or cohort.
Source Year Carriers Unaffected LQT3 BrS1 Other Other Disease
29325976 2018 3 0 3 0
Literature, cohort, and gnomAD 3 0 0 3
Variant features alone 15 11 0 4

Totals may differ from individual publications due to duplicate patients removed during curation.

Functional data

Peak and late/persistent current values are relative to wild-type (100% indicates no change). V1/2 activation and inactivation denote the membrane potentials (mV) at which half-maximal current is achieved.

Published electrophysiology measurements.
PubMed ID Year Cell Type Peak Current (% WT) V1/2 Activation (mV) V1/2 Inactivation (mV) Late/Persistent Current (% WT)
29325976 2018

Nearby variants

Neighbouring residues within 15 Ångström provide structural context. Variants listed in the right-most column have been observed clinically or in gnomAD.

Previously observed variants near G1548K.
Neighbour residue Distance (Å) Observed variants
277 15
271 12 L271V,
266 9 L266H,
1544 7 T1544P,
270 7 Q270K,
360 15
1627 13
1567 14 F1567L, F1567L, F1567L,
1624 14 V1624I,
1552 8 Q1552R, Q1552L,
355 12 F355I, F355C,
1549 5
1556 8
356 9 D356N,
1543 10 V1543L, V1543L, V1543A,
1558 12
1542 11
1557 8 I1557V,
361 12
1562 14
1564 11
354 14
1546 7 M1546T,
1545 6
1626 12 R1626C, R1626H, R1626P, R1626L
267 12
1550 9
1560 7 L1560F, L1560F,
262 14 S262G,
357 9
272 13
274 12 G274C,
273 7
1559 11 I1559V,
1553 10 S1553R, S1553R, S1553R,
269 7
1620 14 T1620K, T1620M,
275 14 N275K, N275K,
1548 0 E1548K, G1548K,
1555 13 E1555K,
265 12 A265V,
1619 13 P1619Q, P1619L, c.4856delC,
358 10
1551 9 D1551N, D1551Y,
263 15 V263I,
359 13 A359T, p.A359PfsX12,
1547 5 V1547L, V1547L,
1563 11
1541 11
1554 12
1540 14
268 11 G268S,
1622 14
1561 11
1623 10 c.4867delC, R1623X, R1623Q, R1623L,