KCNQ1 Variant V524G Detail

We estimate the penetrance of LQTS for KCNQ1 V524G is 79%. This variant was found in a total of 6 carriers in 7 papers or gnomAD, 6 had LQTS. V524G is not present in gnomAD. V524G has not been functionally characterized. This residue is located in a Hotspot region for LQT1. In silico predictions, functional data (if available), and location in structure are equivalent to observing 6 individuals with LQT1 and 4 unaffected individuals. These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 V524G around 79% (12/16).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-6.0 0.992 -1 0.941 76
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
32893267 2020 6 None 6 None
22949429 2012 6 None 6 None
21964171 2011 1 None None Drowning
19841300 2009 6 None 6 None
19716085 2009 1 None 1 None
17470695 2007 4 None 4 None
14678125 2003 1 None 1 None
LITERATURE, COHORT, AND GNOMAD: - 6 0 6
VARIANT FEATURES ALONE: - 10 4 6 -
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.

V524G has 34 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
524 0 V524G,
525 4 A525T, A525V,
528 5
527 6
523 6
521 6
526 7 K526Q, K526E,
522 7 Y522S,
520 8 M520R,
373 8 S373P,
374 9 L374H, L374F,
377 9
530 10
370 10 A370V,
529 10
519 11 R519H, R519C,
517 11 I517T,
531 11
371 12 A371T,
543 12 E543K,
378 12 A378T,
376 12
372 12
380 12 R380S, R380S, R380G,
547 12 Q547R,
532 12
518 12 R518Q, R518G,
381 13 C381Y,
516 13
369 13
375 13
534 14
533 15 R533W, R533Q,
546 15 S546L, S546W,