KCNH2 Variant T1082S Detail

We estimate the penetrance of LQTS for KCNH2 T1082S is 8%. We are unaware of any observations of this variant in individuals. T1082S is not present in gnomAD. We have tested the trafficking efficiency of this variant, 107% of WT with a standard error of 4%; in our analysis we used SE < 20% as 'high quality'. Approximately below 50% of WT is considered PS3 moderate and below 30% is PS3 strong. T1082S 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 T1082S around 8% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-0.613 0.012 4 0.468 2
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.

T1082S 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
1082 0
1081 4
1083 4 T1083fsX, T1083A,
1080 5
1084 5 P1084R, P1084L, P1084X,
1079 7 S1079N,
1085 7 G1085X,
1078 8 Y1078C,
1086 8 P1086fsX, P1086X,
1077 8 A1077D, A1077T,
1087 8 G1087X,
1076 9
1088 9
1075 10 P1075L,
1089 10 T1089I, T1089A,
1074 11
1090 11 S1090F,
1073 11 L1073P,
1091 11
1072 12 T1072S, T1072M,
1092 12 S1092F,
1071 13 M1071V,
1093 13 P1093R, P1093L,
1070 13 Q1070P, Q1070X,
1094 13 L1094M,
1069 14 R1069S, R1069S,
1095 14
1068 14 Q1068R, Q1068X,
1096 14
1067 15
1097 15 V1097I,