KCNH2 Variant S631T Detail

We estimate the penetrance of LQTS for KCNH2 S631T is 79%. We are unaware of any observations of this variant in individuals. S631T is not present in gnomAD. S631T has not been functionally characterized. This residue is located in a Hotspot region for LQT2. In silico predictions, functional data (if available), and location in structure are equivalent to observing 7 individuals with LQT2 and 3 unaffected individuals.These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 S631T around 79% (7/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-2.85 0.993 1 0.802 91
PROVEAN scores less than -2 are considered deleterious. REVEL scores higher than 0.5 or 0.75 are considered likely pathogenic (higher sensitivity with the former cutoff, higher specificity with the latter cutoff). A PolyPhen-2 score of 0.85 or greater is considered likely pathogenic. BLAST-PSSM reflects the evolutionary conservation of residue substitutions, more negative numbers indicate fewer observations of the specific substitution than is expected. Penetrance density is our previously published method to calculate the average LQTS probability density in a shell of residues surrounding a residue of interest (Kroncke et al. 2019).

Reported Carrier Data

PubMed ID Year Carriers Unaffected LQT2 Other Disease
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 -
VARIANT FEATURES ALONE: - 10 3 7 -
Summary totals might not agree with the literature table because of duplicate patients, which were excluded from the total counts. We do not distinguish here between multiple missense codons. Missense variants are combined across degenerate codon substitutions since codon-level data were not consistently available for curation.

S631T has 78 previously observed neighbors within 15 angstroms

A residue within a folded protein on average has nearest neighbors that fall roughly into two shells: a "nearest" neighbor around 5-6 angstroms and a second shell around 11 angstroms. NOTE: 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 15A window. All variants shown in the rightmost column have been observed in at least one individual in the literature or gnomAD.

Neighbor Distance (Angstroms) Variants Observed in Individuals
631 0 S631F,
632 4 P632A, P632S,
630 4 V630T, V630A, V630I,
629 5 N629K, N629K, N629S, N629D, N629I, N629T,
633 6 N633I, N633S, N633D,
628 6 G628S, G628Del, G628A, G628V, G628R, G628D,
627 6 F627L, F627L, F627L, F627fsX, F627X,
628 7 G628S, G628Del, G628A, G628V, G628R, G628D,
585 7 W585C, W585C,
617 7 F617L, F617L, F617L, F617V,
637 7 E637X, E637G, E637K,
629 7 N629K, N629K, N629S, N629D, N629I, N629T,
588 8 N588K, N588K, N588D,
584 8 G584R, G584C, G584S,
638 8 K638E, K638D, K638R, K638Del,
568 9 W568C, W568C,
616 9 Y616S,
634 9 T634S, T634P, T634I, T634A, T634S,
626 9 G626S, G626V, G626A,
641 9 S641F, S641P,
592 10 Q592X,
630 10 V630T, V630A, V630I,
626 10 G626S, G626V, G626A,
627 10 F627L, F627L, F627L, F627fsX, F627X,
589 10 L589P,
616 10 Y616S,
613 10 T613L, T613A, T613M, T613K,
621 11 S621R, S621N, S621R, S621R,
620 11 S620I, S620G,
592 11 Q592X,
586 11 L586M,
614 11 A614V, A614T,
640 11 F640L, F640L, F640L, F640V, F640Del,
583 11 I583V,
625 12 V625E,
636 12
618 12 T618S, T618S,
613 12 T613L, T613A, T613M, T613K,
628 12 G628S, G628Del, G628A, G628V, G628R, G628D,
620 12 S620I, S620G,
635 12 N635I,
587 12
593 12 I593V, I593R, I593T, I593K, I593X,
571 12 I571L, I571V,
631 12 S631F,
631 12 S631F,
625 13 V625E,
632 13 P632A, P632S,
628 13 G628S, G628Del, G628A, G628V, G628R, G628D,
645 13 M645I, M645L, M645V, M645I, M645I, M645L, M645R,
572 13 G572C, G572R, G572D, G572S,
591 13 D591H, D591N,
589 13 L589P,
633 13 N633I, N633S, N633D,
642 13 I642V, I642Del,
639 13 I639F, I639N,
644 13 V644F, V644I,
626 13 G626S, G626V, G626A,
617 13 F617L, F617L, F617L, F617V,
590 13 G590D, G590V,
627 13 F627L, F627L, F627L, F627fsX, F627X,
588 13 N588K, N588K, N588D,
638 13 K638E, K638D, K638R, K638Del,
626 14 G626S, G626V, G626A,
612 14 V612L, V612A, V612L,
565 14
615 14 L615F, L615V,
629 14 N629K, N629K, N629S, N629D, N629I, N629T,
624 14 S624R, S624N, S624R, S624R,
593 15 I593V, I593R, I593T, I593K, I593X,
569 15 Y569X, Y569C, Y569H,
612 15 V612L, V612A, V612L,
610 15
564 15 L564L,
614 15 A614V, A614T,
622 15 L622F,
591 15 D591H, D591N,
619 15