SCN5A Variant S321Y

Summary of observed carriers, functional annotations, and structural context for SCN5A S321Y. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT3 penetrance

3%

0/11 effective observations

Estimated BrS1 penetrance

50%

5/11 effective observations

Total carriers

1

1 BrS1 · 0 LQT3 · 0 unaffected

S321Y 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 (%)
-2.55 0.667 -0.76 0.551 65 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
25401102 2014 1 0 1 0
Literature, cohort, and gnomAD 1 0 0 1
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)
25401102 2014

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 S321Y.
Neighbour residue Distance (Å) Observed variants
343 14
277 12
350 14 H350Q, H350Q,
341 14 C341Y,
342 12
326 13
276 15 L276Q, L276P,
339 13
346 8 E346K, E346G, E346X, E346D, E346D,
319 7 G319S, G319R, G319C,
325 12 L325R,
348 11 P348A,
317 10 K317E, K317M, K317N, K317N,
282 11 R282C, R282H,
279 7
324 10
321 0 S321Y,
344 9 A344S,
872 12 D872N,
340 15 R340W, R340Q,
285 14 T285K,
345 8
322 4
278 13 H278D, H278R,
380 15
873 14 S873A
280 9 C280Y,
349 12 D349N,
318 10
281 9 V281M,
323 6
347 11
283 14
351 13 G351S, G351C, G351D, G351V,
320 4 T320N,