SCN5A Variant V281M

Summary of observed carriers, functional annotations, and structural context for SCN5A V281M. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT3 penetrance

1%

0/13 effective observations

Estimated BrS1 penetrance

34%

4/13 effective observations

Total carriers

3

1 BrS1 · 0 LQT3 · 2 unaffected

V281M is present in 2 alleles 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 3 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 (%)
-1.52 0.999 -1.44 0.724 50 1

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
24775617 2013 1 0 1 0
Literature, cohort, and gnomAD 3 2 0 1
Variant features alone 15 12 0 3

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)
24775617 2013

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 V281M.
Neighbour residue Distance (Å) Observed variants
343 11
328 13
277 13
341 7 C341Y,
274 15 G274C,
342 5
326 9
335 10 C335S, C335R, C335S,
327 11
339 6
346 13 E346K, E346G, E346X, E346D, E346D,
319 8 G319S, G319R, G319C,
384 14 S384T
325 11 L325R,
348 15 P348A,
317 11 K317E, K317M, K317N, K317N,
284 10
336 10 P336L,
282 6 R282C, R282H,
279 6
324 11
321 9 S321Y,
344 8 A344S,
340 6 R340W, R340Q,
338 8
285 11 T285K,
345 10
322 12
278 10 H278D, H278R,
334 13 c.999-424_1338+81del,
383 14
280 5 C280Y,
318 11
281 0 V281M,
323 9
347 15
283 6
337 13
286 14 A286S, A286V,
320 7 T320N,