KCNQ1 Variant A302V

Summary of observed carriers, functional annotations, and structural context for KCNQ1 A302V. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

72%

13/19 effective observations

Total carriers

9

6 LQT1 · 3 unaffected

Functional studies

1

Publications with functional data

A302V is present in 1 alleles 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 (%)
-3.89 1.0 -3 0.932 81

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
26496715 2016 3 None 3 None
25786344 2015 1 1 None None
24606995 2014 1 None 1 None
24144883 2014 1 1 None Early onset AF
23631430 2013 2 None None None
22677073 2012 1 None None SUDS
19808498 2009 1 None 1 None
19716085 2009 1 None 1 None
19490272 2009 1 None 1 None
17222736 2007 1 None None None
Literature, cohort, and gnomAD 9 3 6
Variant features alone 15 3 7

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

Functional data

Functional assay results from published electrophysiology studies. HM indicates homomeric channels, HT indicates heteromeric channels.

Homomeric channel data

Published electrophysiology measurements (homomeric).
PubMed ID Year Study Type Assay Temperature Cell Type Result

Heteromeric channel data

Published electrophysiology measurements (heteromeric).
PubMed ID Year Study Type Assay Temperature Cell Type Result

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 A302V.
Neighbour residue Distance (Å) Observed variants
302 0 A302V, A302E, A302T,
303 4 L303P,
301 5
277 5 S277L, S277del, S277P, S277W,
300 5 A300T, A300S,
299 5
296 6 F296S, F296L, F296L, F296L,
306 6 G306V, G306R, G306R,
281 6 Y281C,
298 7 S298I, S298N,
276 8 S276del,
297 8 G297S, G297D, G297R,
273 9 L273F, L273V, L273R,
274 9 I274V,
278 9 Y278H,
141 10 V141M,
279 10 F279I,
282 11 L282P,
144 11 T144A,
285 11
294 11 V294M,
275 12 F275del,
145 12
231 12 R231C, R231H, R231S,
272 12 G272D, G272S, G272V,
326 12
287 12 A287E, A287T, A287S,
320 13 P320H, P320A, P320S,
140 13 S140G, S140R, S140R, S140R,
304 13 W304R, W304R,
315 13 Y315C, Y315S, Y315N, Y315H, Y315F
329 13 A329T,
235 13 I235N,
319 13 V319L, V319L,
325 13 G325R, G325R, G325E, G325W,
293 13 R293C, R293H,
330 14
286 14
137 14 L137F, L137P,
270 14 F270S,
142 14
327 14 T327A, T327S, T327S,
143 14 S143F, S143P, S143Y,
280 14 V280A, V280E,
321 14
138 14
322 15 T322M, T322A, T322K,
271 15
328 15 I328del,
232 15
307 15 V307L, V307L,
228 15
288 15