KCNH2 Variant E939D Detail

We estimate the penetrance of LQTS for KCNH2 E939D is 8%. We are unaware of any observations of this variant in individuals. E939D is not present in gnomAD. E939D has not been functionally characterized. This residue is located in a Non_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 E939D around 8% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-0.703 0.001 1 0.456 7
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.

E939D 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
939 0
938 4
940 4
937 5 S937N,
941 5
936 7
942 7
935 8
943 8
934 8
944 8 E944D, E944D,
933 9
945 9
932 10
946 10 P946R, P946fsX,
931 11 P931L,
947 11 G947D,
930 11
948 11 R948C, R948S, R948H,
929 12
949 12 S949R, S949R, S949R,
928 13 G928fsX, G928E,
950 13
927 13 W927G, W927C, W927C, W927X, W927S, W927L,
951 13
926 14 P926fsX, P926X, P926L, P926S,
952 14 P952S, P952T,
925 14 G925E, G925X, G925R, G925V, G925fsX, G925R, G925A,
953 14
924 15 G924X, G924W, G924V, G924E, G924A,
954 15 R954H, R954C,