SCN5A Variant Q245K

Summary of observed carriers, functional annotations, and structural context for SCN5A Q245K. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT3 penetrance

52%

5/15 effective observations

Estimated BrS1 penetrance

5%

0/15 effective observations

Total carriers

5

0 BrS1 · 3 LQT3 · 2 unaffected

Q245K is present in 2 alleles in gnomAD. This residue resides in a Non_Hotspot region for Brugada syndrome and a Hotspot region for LQT3.

Variant features alone are equivalent to phenotyping 0 individuals for Brugada syndrome and 2 individuals for LQT3.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.4 0.953 2.39 0.906 1 56

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
15840476 2005 1 1 0 0
27566755 2016 3 3 0 0
Literature, cohort, and gnomAD 5 2 3 0
Variant features alone 15 13 2 0

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)
25904541 2015 HEK 84 -4 1
15840476 2005
27566755 2016

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 Q245K.
Neighbour residue Distance (Å) Observed variants
414 9 M414V,
249 5 K249X,
247 7 V247L, V247L,
240 9 V240M,
254 14
193 14 W193R, W193R, W193X,
418 8 E418K,
250 9
409 14 L409V, L409P,
237 12
928 15 L928P,
925 14 I925F,
417 12
933 12
246 5
1779 14 T1779M
412 9 V412D,
924 15 V924I,
245 0 Q245K,
244 5
415 6 A415T,
420 13
248 5
241 6
419 8 Q419X,
930 14 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
423 14
239 11 I239V, I239V ,
251 11
410 13 A410V,
242 6 A242D,
929 11
416 10 Y416C,
413 11 A413T, A413E,
236 14
408 13
253 13
192 15
936 14
238 11
422 12
1775 15 F1775V, p.F1775LfsX15,
1642 14 G1642E,
421 14
252 13
411 9 V411M,
243 7
932 14