SCN5A Variant I397V

Summary of observed carriers, functional annotations, and structural context for SCN5A I397V. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT3 penetrance

28%

1/12 effective observations

Estimated BrS1 penetrance

25%

2/12 effective observations

Total carriers

2

1 BrS1 · 0 LQT3 · 1 unaffected

I397V is present in 1 alleles in gnomAD. This residue resides in a Mild_Hotspot region for Brugada syndrome and a Hotspot region for LQT3.

Variant features alone are equivalent to phenotyping 1 individuals for Brugada syndrome and 1 individuals for LQT3.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-0.98 0.993 3.05 0.896 28 53

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
25650408 2015 1 0 1 0
Literature, cohort, and gnomAD 2 1 0 1
Variant features alone 15 13 1 1

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)
25650408 2015

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 I397V.
Neighbour residue Distance (Å) Observed variants
403 9
364 12
1702 14
363 15
404 10 L404V, L404Q,
1765 15
396 4 V396L, V396A,
355 15 F355I, F355C,
391 11
372 11
1771 15 I1771T
401 5 S401P,
1764 11 c.5290delG, V1764F,
371 6 Q371E,
1711 12 c.5131delG,
260 12
366 11
1707 13
365 9
1704 14 L1704H,
1706 11 Q1706H, Q1706H,
897 15 G897R, G897R, G897E,
1668 14 M1668T,
369 7 M369K,
1767 11 Y1767C,
1660 14 I1660V, I1660S,
378 10
402 6 F402L, F402L, F402L,
373 13
1768 14 I1768V,
267 14
379 15
399 7
397 0 I397V, I397F, I397T,
405 10
1657 13
362 15
1759 14 S1759C,
261 12
1709 8 p.T1709del, T1709R, T1709M,
1701 15 M1701I, M1701I, M1701I,
392 9
389 14 Y389H, Y389X,
395 7
393 7
390 11
394 7
264 10
1708 10 T1708I,
382 15
265 14 A265V,
374 7 W374G,
1705 9
407 15
367 11 R367C, R367H, R367L,
1763 14 V1763M, V1763L, V1763L,
263 14 V263I,
1760 14
370 9 T370M,
1661 12 G1661R, G1661R, G1661E,
381 14 c.1140+1G>A, c.1141-3C>A,
375 13
406 12 N406S, N406K, N406K,
368 6
1710 12 S1710L,
268 14 G268S,
377 11
398 6
257 14
400 6 G400R, G400R, G400E, G400A,
1664 12
1658 14