KCNQ1 Variant T312I

Summary of observed carriers, functional annotations, and structural context for KCNQ1 T312I. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

84%

10/13 effective observations

Total carriers

3

3 LQT1 · unaffected

Functional studies

3

Publications with functional data

T312I 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 (%)
-5.54 1.0 1 0.982 92

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
27114410 2016 1 None None None
23631430 2013 3 None None None
23153844 2012 17 None 1 None
22949429 2012 1 None 1 None
22677073 2012 1 None None SUDS
19841300 2009 1 None 1 None
19716085 2009 2 None 2 None
19490272 2009 17 None 17 None
17470695 2007 14 None 14 None
17192539 2006 1 None 1 None
14678125 2003 13 None 13 None
Literature, cohort, and gnomAD 3 3
Variant features alone 15 3 7

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