KCNQ1 Variant L619M

Summary of observed carriers, functional annotations, and structural context for KCNQ1 L619M. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

75%

8/11 effective observations

Total carriers

1

1 LQT1 · 0 unaffected

Functional studies

1

Publications with functional data

L619M 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 (%)
-0.39 0.003 1 0.553 75

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
25344363 2014 None None None None
22949429 2012 1 None 1 None
19841300 2009 1 None 1 None
Literature, cohort, and gnomAD 1 0 1
Variant features alone 15 3 7

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

Functional data

Functional assay results from published electrophysiology studies. HM indicates homomeric channels, HT indicates heteromeric channels.

Homomeric channel data

Published electrophysiology measurements (homomeric).
PubMed ID Year Study Type Assay Temperature Cell Type Result

Heteromeric channel data

Published electrophysiology measurements (heteromeric).
PubMed ID Year Study Type Assay Temperature Cell Type Result

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 L619M.
Neighbour residue Distance (Å) Observed variants
619 0 L619M,
618 4
620 4
617 5
621 5 G621S, G621C, G621D,
616 7
622 7 G622S,
615 8
623 8
614 8 H614del,
624 8
613 9
625 9 P625R,
612 10
626 10 G626S,
611 11 D611N, D611Y,
627 11
610 11
628 11 G628S, G628D,
609 12
629 12 G629S,
608 13
630 13 P630S, P630T
607 13 A607T,
631 13 P631R,
606 14
632 14
605 14
633 14
604 15
634 15