KCNH2 Variant E929D Detail

We estimate the penetrance of LQTS for KCNH2 E929D is 9%. We are unaware of any observations of this variant in individuals. E929D is not present in gnomAD. E929D has not been functionally characterized. This residue is located in a Mild_Hotspot region for LQT2. In silico predictions, functional data (if available), and location in structure are equivalent to observing 0 individuals with LQT2 and 10 unaffected individuals.These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 E929D around 9% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-0.725 0.0 1 0.457 11
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 10 0 -
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.

E929D has 31 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
929 0
928 4 G928fsX, G928E,
930 4
927 5 W927X, W927S, W927C, W927L, W927G, W927C,
931 5 P931L,
926 7 P926fsX, P926X, P926S, P926L,
932 7
925 8 G925E, G925R, G925V, G925fsX, G925R, G925A, G925X,
933 8
924 8 G924E, G924X, G924A, G924V, G924W,
934 8
923 9 P923X, P923L, P923fsX, P923Q,
935 9
922 10 R922Q, R922W, R922fsX,
936 10
921 11
937 11 S937N,
920 11 R920Q, R920G, R920fsX, R920W,
938 11
919 12
939 12
918 13
940 13
917 13 P917L,
941 13
916 14
942 14
915 14 A915V, A915fsX, A915X,
943 14
914 15
944 15 E944D, E944D,