KCNQ1 Variant S277W

Summary of observed carriers, functional annotations, and structural context for KCNQ1 S277W. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

78%

8/11 effective observations

Total carriers

1

1 LQT1 · 0 unaffected

Functional studies

0

Publications with functional data

S277W has not been reported in gnomAD. This residue resides in a Hotspot region for LQT1.

Variant features alone are equivalent to phenotyping 7 individuals with LQT1 and 3 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT1 (%)
-6.8 1.0 -4 0.979 85

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. BLAST-PSSM reflects evolutionary conservation; more negative values indicate rarer substitutions. Penetrance density summarises neighbouring residue risk (Kroncke et al. 2019).

Reported carrier data

Observed carriers by publication or cohort.
Source Year Carriers Unaffected LQT1 Other Disease
32893267 2020 1 None 1 None
17192539 2006 1 None 1 None
Literature, cohort, and gnomAD 1 0 1
Variant features alone 15 3 7

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

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 S277W.
Neighbour residue Distance (Å) Observed variants
277 0 S277L, S277del, S277P, S277W,
276 4 S276del,
302 5 A302V, A302E, A302T,
303 5 L303P,
280 5 V280A, V280E,
273 6 L273F, L273V, L273R,
274 6 I274V,
299 6
278 6 Y278H,
279 7 F279I,
275 7 F275del,
272 8 G272D, G272S, G272V,
281 8 Y281C,
300 9 A300T, A300S,
296 9 F296S, F296L, F296L, F296L,
282 9 L282P,
301 9
235 10 I235N,
283 10 A283G, A283T,
298 10 S298I, S298N,
284 10 E284K,
271 10
231 11 R231C, R231H, R231S,
270 11 F270S,
141 11 V141M,
232 11
318 11
269 11 G269D, G269S, G269del,
297 12 G297S, G297D, G297R,
137 12 L137F, L137P,
285 12
144 12 T144A,
140 13 S140G, S140R, S140R, S140R,
295 13
238 13 M238V, M238L, M238L,
330 13
234 13 Q234H, Q234H,
329 13 A329T,
236 14 L236Q, L236R,
228 14
229 14 G229D,
326 14
327 14 T327A, T327S, T327S,
333 14
307 15 V307L, V307L,
304 15 W304R, W304R,
138 15
315 15 Y315C, Y315S, Y315N, Y315H, Y315F
268 15 I268V, I268S,
328 15 I328del,
313 15
308 15 V308F,
331 15
287 15 A287E, A287T, A287S,
145 15
325 15 G325R, G325R, G325E, G325W,