KCNQ1 Variant L342F

Summary of observed carriers, functional annotations, and structural context for KCNQ1 L342F. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

85%

13/16 effective observations

Total carriers

6

6 LQT1 · unaffected

Functional studies

1

Publications with functional data

L342F has not been reported in gnomAD. This residue resides in a Hotspot region for LQT1.

Variant features alone are equivalent to phenotyping 7 individuals with LQT1 and 3 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT1 (%)
-3.66 1.0 1 0.876 85

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
32893267 2020 2 None 2 None
32893267 2020 1 None 1 None
27041096 2016 1 None 1 None
24217263 2013 1 None 1 None
19716085 2009 2 None 2 None
18752142 2008 4 None 1 RWS
17192539 2006 1 None 1 None
Literature, cohort, and gnomAD 6 6
Variant features alone 15 3 7

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