KCNQ1 Variant K422T
Summary of observed carriers, functional annotations, and structural context for KCNQ1 K422T. Data combine curated literature, international cohorts, and gnomAD observations.
Estimated LQT1 penetrance
19%
2/13 effective observations
Total carriers
3
1 LQT1 · 2 unaffected
Functional studies
0
Publications with functional data
Variant features alone are equivalent to phenotyping 1 individuals with LQT1 and 9 unaffected individuals.
In silico predictors
| PROVEAN | PolyPhen-2 | BLAST-PSSM | REVEL | Penetrance Density LQT1 (%) |
|---|---|---|---|---|
| -1.77 | 0.23 | 0 | 0.687 | 17 |
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
| Source | Year | Carriers | Unaffected | LQT1 | Other Disease |
|---|---|---|---|---|---|
| 30758498 | 2019 | 3 | None | 3 | None |
| 23995305 | 2013 | 4 | None | 1 | None |
| Literature, cohort, and gnomAD | – | 3 | 2 | 1 | – |
| 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.
| Neighbour residue | Distance (Å) | Observed variants |
|---|---|---|
| 422 | 0 | K422T, K422R, |
| 421 | 4 | K421N, K421N, |
| 423 | 4 | |
| 420 | 5 | K420E, K420N, K420N, |
| 424 | 5 | K424T, |
| 419 | 7 | |
| 425 | 7 | L425V, |
| 418 | 8 | V418I, |
| 426 | 8 | |
| 417 | 8 | V417M, |
| 427 | 8 | |
| 416 | 9 | V416M, |
| 428 | 9 | D428G, |
| 415 | 10 | |
| 429 | 10 | N429S, |
| 414 | 11 | |
| 430 | 11 | |
| 413 | 11 | K413R, |
| 431 | 11 | V431L, V431L, |
| 412 | 12 | P412S, |
| 432 | 12 | T432I, T432A |
| 411 | 13 | |
| 433 | 13 | P433A, |
| 410 | 13 | |
| 434 | 13 | G434R, G434R, |
| 409 | 14 | |
| 435 | 14 | |
| 408 | 14 | P408A, |
| 436 | 14 | |
| 407 | 15 | |
| 437 | 15 | M437V, |