KCNH2 Variant V956L Detail

We estimate the penetrance of LQTS for KCNH2 V956L is 8%. We are unaware of any observations of this variant in individuals. V956L is not present in gnomAD. V956L 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 V956L around 8% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-0.389 0.118 1 0.434 1
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.

V956L 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
956 0
955 4 L955V,
957 4
954 5 R954H, R954C,
958 5 F958L, F958L, F958L,
953 7
959 7
952 8 P952S, P952T,
960 8 S960N,
951 8
961 8 P961X,
950 9
962 9
949 10 S949R, S949R, S949R,
963 10 P963T,
948 11 R948S, R948H, R948C,
964 11 G964X,
947 11 G947D,
965 11 G965R, G965fsX, G965R, G965X,
946 12 P946fsX, P946R,
966 12 E966A, E966K,
945 13
967 13 P967X, P967L,
944 13 E944D, E944D,
968 13 P968fsX, P968L, P968A,
943 14
969 14 G969X, G969D,
942 14
970 14 G970A,
941 15
971 15