KCNQ1 Variant H442R

Summary of observed carriers, functional annotations, and structural context for KCNQ1 H442R. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

9%

1/11 effective observations

Total carriers

1

0 LQT1 · 1 unaffected

Functional studies

0

Publications with functional data

H442R is present in 1 alleles in gnomAD. This residue resides in a Non_Hotspot region for LQT1.

Variant features alone are equivalent to phenotyping 1 individuals with LQT1 and 9 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT1 (%)
-0.79 0.004 -1 0.606 2

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 LQT1 Other Disease
Literature, cohort, and gnomAD 1 1 0
Variant features alone 15 9 1

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

Nearby variants

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

Previously observed variants near H442R.
Neighbour residue Distance (Å) Observed variants
442 0 H442R,
441 4 P441S,
443 4
440 5
444 5 T444M, T444K
439 7
445 7
438 8
446 8 D446E, D446E, D446E, D446E, D446N,
437 8 M437V,
447 8 P447H,
436 9
448 9 P448R, P448Q, P448L, P448S,
435 10
449 10 E449K,
434 11 G434R, G434R,
450 11 E450K,
433 11 P433A,
451 11 R451Q, R451W,
432 12 T432I, T432A,
452 12 R452Q, R452W, R452L,
431 13 V431L, V431L,
453 13
430 13
454 13
429 14 N429S,
455 14 H455Y, H455Q, H455Q, H455R,
428 14 D428G,
456 14 F456L, F456L, F456L,
427 15
457 15