KCNQ1 Variant F339C

Summary of observed carriers, functional annotations, and structural context for KCNQ1 F339C. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

70%

7/10 effective observations

Total carriers

0

0 LQT1 · 0 unaffected

Functional studies

0

Publications with functional data

F339C 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 (%)
-7.43 1.0 3 0.946 77

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 0 0 0
Variant features alone 15 3 7

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 F339C.
Neighbour residue Distance (Å) Observed variants
271 10
250 11 L250H, L250P,
266 12 L266P,
247 12 T247I,
262 12 L262P, L262R, L262V,
248 12 W248C, W248C, W248R, W248R
276 13 S276del,
255 13
274 13 I274V,
275 13 F275del,
270 14 F270S,
254 14 V254M, V254L, V254L,
252 14 G252R,
263 14
339 15 F339del, F339S,
341 15 A341V, A341E,
258 15 H258P, H258N, H258R, H258Y,
334 15 V334A,