KCNH2 Variant Q11L Detail

We estimate the penetrance of LQTS for KCNH2 Q11L is 8%. This variant was found in a total of 2 carriers in 0 papers or gnomAD (version 4), 0 had LQTS. Q11L is present in 2 alleles in gnomAD. We have tested the trafficking efficiency of this variant, 106% of WT with a standard error of 12%; 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. Q11L 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 Q11L around 8% (0/12).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-3.887 0.272 -3 0.764 3
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: - 2 1 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.

Q11L has 45 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
11 0 Q11L, Q11H, Q11H,
12 4 N12D,
10 5
13 7 T13N,
9 7 A9T, A9V,
14 8
8 9
793 9 D793N,
823 10 R823fsX, R823W, R823Q, R823T,
825 10
15 10 L15V,
795 10 V795I,
788 10 E788D, E788D, E788K,
766 10
7 11
790 11
824 11
794 11 V794D, V794I,
123 12
765 12
117 12
792 12
16 13 D16A,
124 13 M124R, M124T,
17 13
826 13 T826I, T826A,
767 14 D767X,
118 14 E118X, E118D, E118K, E118D,
786 14
789 14
33 14 N33T,
797 14 A797T,
821 14 D821E, D821E,
798 14 I798fsX,
482 14 V482A,
822 14 V822M, V822L, V822L,
768 14
796 14 V796L, V796Del, V796L,
787 14
115 14 V115M,
18 14 I18M,
119 15 D119G, D119H,
121 15 A121fsX,
35 15 R35W,
481 15