KCNQ1 Variant P477T

Summary of observed carriers, functional annotations, and structural context for KCNQ1 P477T. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

37%

4/11 effective observations

Total carriers

1

0 LQT1 · 1 unaffected

Functional studies

0

Publications with functional data

P477T is present in 1 alleles in gnomAD. This residue resides in a Hotspot region for LQT1.

Variant features alone are equivalent to phenotyping 4 individuals with LQT1 and 6 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT1 (%)
-1.2 0.0 1 0.419 43

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
Literature, cohort, and gnomAD – 1 1 0 –
Variant features alone – 15 6 4 –

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 P477T.
Neighbour residue Distance (Å) Observed variants
477 0 P477L, P477T,
476 4 M476L, M476L, M476V,
478 4 H478Y,
475 5
479 5 F479L, F479L, F479L,
474 7
480 7 M480T,
473 8 E473Q,
481 8
472 8 L472P,
482 8 T482N, T482A, T482S, T482S,
471 9
483 9
470 10
484 10
469 11
485 11 F485S,
468 11 S468G, S468N,
486 11 A486T,
467 12 K467R,
487 12 E487K,
466 13
488 13 D488E, D488E,
465 13
489 13
464 14 S464P,
490 14
463 14 S463T,
491 14
462 15 D462N
492 15 L492ins,