KCNH2 Variant Q61P Detail

We estimate the penetrance of LQTS for KCNH2 Q61P is 76%. We are unaware of any observations of this variant in individuals. Q61P is not present in gnomAD. Q61P has not been functionally characterized. This residue is located in a Hotspot region for LQT2. In silico predictions, functional data (if available), and location in structure are equivalent to observing 7 individuals with LQT2 and 3 unaffected individuals.These data combined with observations of carriers lead us to estimate the LQTS penetrance for KCNQ1 Q61P around 76% (7/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density (%)
-4.067 0.254 -2 0.836 80
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 3 7 -
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.

Q61P has 55 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
61 0 Q61R,
60 5 M60T,
62 6 R62Q,
860 7
40 7
41 7 V41A,
796 7 V796L, V796Del, V796L,
59 8
57 8 A57P,
42 8 I42N,
63 9 P63H,
861 9 N861H, N861I,
797 9 A797T,
859 9 T859M, T859R,
58 10 E58D, E58D, E58K,
789 10
791 10 R791W, R791Q,
38 10
819 10 N819K, N819K,
862 11 L862P,
39 11 C39X, C39R,
56 11 R56Q,
36 11 V36X,
44 11 C44X, C44F, C44W,
32 11 A32T,
858 12 I858T, I858V,
33 12 N33T,
798 12 I798fsX,
64 12 C64Y, C64R,
795 12 V795I,
55 12 S55L,
37 12
799 12 L799sp,
863 12 R863P, R863X,
31 12 I31S,
794 12 V794I, V794D,
43 13 Y43C, Y43D,
68 13 F68V, F68L, F68L, F68L,
66 13 C66G, C66Y, C66R,
820 13 G820R, G820R,
806 13 G806R, G806R,
790 13
30 13 I30T, I30Del,
805 14 F805S, F805C,
857 14 E857X,
65 14 T65P,
54 14 Y54X, Y54N,
788 14 E788D, E788K, E788D,
67 14
804 14
807 14 E807X,
35 14 R35W,
34 14 A34T,
803 14 D803Y, D803X,
818 15 S818A, S818L, S818W,