KCNQ1 Variant A590T

Summary of observed carriers, functional annotations, and structural context for KCNQ1 A590T. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

33%

6/20 effective observations

Total carriers

10

2 LQT1 · 8 unaffected

Functional studies

1

Publications with functional data

A590T is present in 3 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 (%)
-1.81 0.89 -1 0.817 46

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 2 None 2 None
28491806 2017 4 4 None None
22949429 2012 1 None 1 None
19841300 2009 1 None 1 None
17192539 2006 1 None 1 None
14998624 2004 1 1 None None
Literature, cohort, and gnomAD 10 8 2
Variant features alone 15 6 4

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 A590T.
Neighbour residue Distance (Å) Observed variants
590 0 A590T,
589 4 G589D, G589S,
591 4 R591H, R591C, R591L,
588 5 I588F,
592 5
587 7 T587M, T587R,
593 7 N593S,
586 8 N586D,
594 8 R594Q, R594P,
585 8 S585N,
595 8 V595L, V595L
584 9 G584S,
596 9 E596del, E596K,
583 10 R583H, R583C, R583G,
597 10
582 11
598 11 K598R,
581 11
599 11
580 12 S580G, S580N,
600 12 T600M,
579 13
601 13
578 13 E578K, E578V,
602 13
577 14
603 14
576 14 V576I,
604 14
575 15
605 15