KCNH2 Variant V716G Detail

We estimate the penetrance of LQTS for KCNH2 V716G is 62%. This variant was found in a total of 1 carriers in 1 papers or gnomAD, 1 had LQTS. V716G is not present in gnomAD. V716G 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 5 individuals with LQT2 and 5 unaffected individuals.These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 V716G around 62% (6/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-6.815 0.999 -3 0.932 58
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
28532774 2017 1 0 1
LITERATURE, COHORT, AND GNOMAD: - 1 0 1 -
VARIANT FEATURES ALONE: - 10 5 5 -
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.

V716G has 52 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
716 0 V716G,
715 4 A715V, A715sp, A715A, A715T,
717 4 L717P,
718 6
720 6
683 6
713 6 M713V,
719 6
714 7
679 7 R679W, R679Q,
712 7 D712N,
680 7
676 9 Q676X, Q676fsX,
711 9 I711V,
725 9 Q725fsX, Q725R,
728 10
697 10 L697X,
701 10
682 10 E682X,
684 11
721 11 P721L,
687 11
724 11 L724X,
677 11 M677T,
686 12
678 12
700 12
729 12
710 12
708 12
675 12
681 13 R681W,
732 13
689 13
726 13
756 13 M756V,
698 13 E698X, E698K,
693 14 L693X,
727 14
709 14
722 14
704 14 A704V, A704T,
712 14 D712N,
694 14 R694C, R694H,
760 14
673 14
731 14 H731R,
685 15 R685C, R685H, R685P,
723 15 C723R, C723G, C723X,
710 15
696 15 R696C, R696H,
707 15