KCNQ1 Variant V310I

Summary of observed carriers, functional annotations, and structural context for KCNQ1 V310I. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

73%

8/11 effective observations

Total carriers

1

1 LQT1 · 0 unaffected

Functional studies

2

Publications with functional data

V310I 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 (%)
-0.6 0.888 2 0.781 74

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
19490272 2009 2 None 2 None
17470695 2007 1 None 1 None
15649981 2005 None None None 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.

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 V310I.
Neighbour residue Distance (Å) Observed variants
310 7 V310I,
312 9 T312del, T312I,
337 9
309 9 T309I, T309R,
311 9 T311A, T311I,
333 10
307 11 V307L, V307L,
336 11 A336S,
306 11 G306V, G306R, G306R,
313 11
274 11 I274V,
335 11 F335L, F335L, F335L,
329 11 A329T,
340 11 F340del, F340L, F340L, F340L, F340S,
330 11
308 11 V308F,
334 12 V334A,
314 12 G314S, G314D, G314C, G314del,
332 12
338 12 S338F,
341 12 A341V, A341E,
271 12
273 12 L273F, L273V, L273R,
268 12 I268V, I268S,
276 13 S276del,
305 13 W305S, W305L, W305C, W305C, W305R, W305R,
331 13
339 13 F339del, F339S,
275 13 F275del,
269 13 G269D, G269S, G269del,
266 14 L266P,
315 14 Y315C, Y315S, Y315N, Y315H, Y315F
272 14 G272D, G272S, G272V,
277 14 S277L, S277del, S277P, S277W,
270 14 F270S,
328 14 I328del,
267 15 Y267C,
303 15 L303P,
304 15 W304R, W304R,
300 15 A300T, A300S,
320 15 P320H, P320A, P320S,
299 15