KCNH2 Variant E365R

Summary of observed carriers, functional annotations, and structural context for KCNH2 E365R. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT2 penetrance

21%

2/10 effective observations

Total carriers

0

0 LQT2 · 0 unaffected

Functional studies

1

Publications with functional data

E365R has not been reported in gnomAD. This residue resides in a Hotspot region for LQT2.

We have tested the trafficking efficiency of this variant: 83% of WT with a standard error of 15%. 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.

Variant features alone are equivalent to phenotyping 2 individuals with LQT2 and 8 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT2 (%)
None None None None 59

PROVEAN scores below -2 suggest deleterious impact. REVEL scores above 0.5–0.75 are often interpreted as likely pathogenic. PolyPhen-2 scores above 0.85 are typically pathogenic. BLAST-PSSM reflects evolutionary conservation; more negative values indicate rarer substitutions. Penetrance density summarises neighbouring residue risk (Kroncke et al. 2019).

Reported carrier data

Observed carriers by publication or cohort.
Source Year Carriers Unaffected LQT2 Other Disease
Literature, cohort, and gnomAD 0 0 0
Variant features alone 10 8 2

Totals may differ from individual publications due to duplicate patients removed during curation.

Functional data

Functional assay results from published electrophysiology studies. Steady state (S.S.) and peak tail current are relative % to wildtype (100% being no different from wildtype). V1/2 activation and inactivation are the voltages at which half of the maximal current is reached, in mV. Recovery from inactivation and deactivation time are ratios of characteristic time constants with wildtype. HM indicates homomeric channels, HT indicates heteromeric channels.

Homomeric channel data

Published electrophysiology measurements (homomeric).
PubMed ID Cell Type S.S Peak (%WT) Peak Tail IKr (%WT) V1/2 Act. V1/2 Inact. Recov. Inact. Deactivation (%WT)
16997865 HEK293 17.0 None None None

Heteromeric channel data

Published electrophysiology measurements (heteromeric).
PubMed ID Cell Type S.S Peak (%WT) Peak Tail IKr (%WT) V1/2 Act. V1/2 Inact. Deactivation (%WT)
16997865 HEK293 None None None

Nearby variants

Neighbouring residues within 15 Ångström provide structural context. Variants listed in the right-most column have been observed clinically or in gnomAD. Note that 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 15Å window.

Previously observed variants near E365R.
Neighbour residue Distance (Å) Observed variants
365 0 E365G,
364 4 K364X,
366 4 R366X, R366Q,
363 5 I363X,
367 5 T367S, T367S,
362 7
368 7 H368Y,
361 8
369 8 N369K, N369K,
360 8
370 8
359 9 I359V,
371 9
358 10
372 10
357 11 E357D, E357D,
373 11
356 11 R356C, R356H,
374 11
355 12 D355G,
375 12
354 13
376 13 Q376sp, Q376R,
353 13 T353S, T353S,
377 13
352 14
378 14
351 14 S351L,
379 14 S379Y,
350 15
380 15 L380X