KCNH2 Variant I583V

Summary of observed carriers, functional annotations, and structural context for KCNH2 I583V. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT2 penetrance

15%

90% CI: 3.6% – 28.4%

2/20 effective observations

Total carriers

10

1 LQT2 · 8 unaffected

Functional studies

0

Publications with functional data

I583V is present in 1 alleles in gnomAD. This residue resides in a Hotspot region for LQT2.

We have tested the trafficking efficiency of this variant: 101% of WT with a standard error of 25%. In our analysis we used SE < 20% as 'high quality'. Approximately below 50% of WT is considered PS3 moderate and below 30% is PS3 strong.

Variant features alone are equivalent to phenotyping 1 individuals with LQT2 and 9 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT2 (%)
-0.823 0.236 3 0.725 44

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 LQT2 Other Disease
Italy Cohort 2020 9 8 1
Literature, cohort, and gnomAD 10 8 1
Variant features alone 10 9 1

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. Note that some residues appear multiple times at different distances since the functional KV11.1 channel (protein product of KCNH2/hERG) is a homotetramer and occasionally the same residue from multiple subunits is present within the 15Å window.

Previously observed variants near I583V.
Neighbour residue Distance (Å) Observed variants
583 0 I583V,
584 4 G584S, G584R, G584C,
587 6
633 7 N633D, N633S, N633I,
634 8 T634P, T634A, T634S, T634S, T634I,
577 8
593 8 I593V, I593K, I593T, I593R, I593X,
588 8 N588D, N588K, N588K,
594 8
576 9
592 9 Q592X,
586 9 L586M,
585 10 W585C, W585C,
637 10 E637K, E637G, E637X,
575 10 E575K,
572 10 G572S, G572R, G572C, G572D,
595 11 K595E, K595N, K595N,
635 11 N635I,
591 11 D591N, D591H,
632 11 P632A, P632S,
597 11 Y597H, Y597C,
631 11 S631F,
636 12
590 12 G590D, G590V,
589 12 L589P,
590 12 G590D, G590V,
591 12 D591N, D591H,
571 12 I571L, I571V,
589 12 L589P,
638 13 K638E, K638D, K638Del, K638R
573 13
629 13 N629D, N629T, N629S, N629I, N629K, N629K,
568 14 W568C, W568C,
630 14 V630I, V630T, V630A,
596 14 P596T, P596S, P596R, P596L,
592 14 Q592X,
609 14 D609N, D609G,
596 14 P596T, P596S, P596R, P596L,
605 15 P605L,
606 15 S606Del, S606P, S606F,
574 15 M574L, M574V, M574L,
588 15 N588D, N588K, N588K,
570 15