KCNQ1 Variant V110L Detail

We estimate the penetrance of LQTS for KCNQ1 V110L is 32%. We are unaware of any observations of this variant in individuals. V110L is not present in gnomAD. V110L has not been functionally characterized. This residue is located in a Mild_Hotspot region for LQT1. In silico predictions, functional data (if available), and location in structure are equivalent to observing 3 individuals with LQT1 and 7 unaffected individuals. These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 V110L around 32% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-1.34 0.107 3 0.634 33
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 LQT1 Other Disease
LITERATURE, COHORT, AND GNOMAD: - 0 0 0
VARIANT FEATURES ALONE: - 10 7 3 -
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.

V110L has 40 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. This results from the fact that the functional KV7.1 channel 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
110 0 V110I,
107 5 Q107H, Q107H,
108 5 G108S,
177 6 S177F,
113 6
114 6
106 6
111 6 Y111C,
112 6
109 6 R109C, R109L,
173 7
174 8 R174H, R174C, R174L,
180 9
115 9 E115A, E115G,
176 9
178 9 A178T, A178del,
122 10 C122Y,
179 10 G179S,
170 10
105 10
117 10 P117L,
116 11
175 11 L175I,
104 11 T104A, T104I,
125 11
121 11
172 11 V172M, V172E,
181 12 R181C,
126 12 H126D,
119 12 G119R, G119V,
169 13 T169M, T169R,
118 13
193 13 F193L, F193L, F193L,
171 13
190 13 R190W, R190Q, R190L,
243 13 R243H, R243C, R243P, R243S,
184 14 Y184S, Y184C, Y184D, Y184H,
166 14 F166V,
244 14
168 15 G168R, G168R, G168R, G168R,