KCNH2 Variant W927R Detail

We estimate the penetrance of LQTS for KCNH2 W927R is 9%. We are unaware of any observations of this variant in individuals. W927R is not present in gnomAD. W927R 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 W927R around 9% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-3.532 0.978 -1 0.766 8
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.

W927R 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
927 0 W927C, W927L, W927G, W927X, W927C, W927S,
926 4 P926X, P926S, P926fsX, P926L,
928 4 G928E, G928fsX,
925 5 G925X, G925A, G925V, G925R, G925E, G925fsX, G925R,
929 5
924 7 G924X, G924E, G924W, G924V, G924A,
930 7
923 8 P923Q, P923fsX, P923X, P923L,
931 8 P931L,
922 8 R922W, R922fsX, R922Q,
932 8
921 9
933 9
920 10 R920fsX, R920Q, R920G, R920W,
934 10
919 11
935 11
918 11
936 11
917 12 P917L,
937 12 S937N,
916 13
938 13
915 13 A915V, A915X, A915fsX,
939 13
914 14
940 14
913 14 A913V,
941 14
912 15 R912W, R912X, R912Q,
942 15