KCNQ1 Variant L273R

Summary of observed carriers, functional annotations, and structural context for KCNQ1 L273R. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

64%

7/11 effective observations

Total carriers

1

1 LQT1 · 0 unaffected

Functional studies

0

Publications with functional data

L273R has not been reported in gnomAD. This residue resides in a Hotspot region for LQT1.

Variant features alone are equivalent to phenotyping 6 individuals with LQT1 and 4 unaffected individuals.

In silico predictors

Variant-level computational predictors.
PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density LQT1 (%)
-5.83 1.0 -3 0.974 67

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
22949429 2012 1 None 1 None
19841300 2009 1 None 1 None
Literature, cohort, and gnomAD 1 0 1
Variant features alone 15 4 6

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 L273R.
Neighbour residue Distance (Å) Observed variants
273 0 L273F, L273V, L273R,
274 4 I274V,
277 6 S277L, S277del, S277P, S277W,
269 6 G269D, G269S, G269del,
303 7 L303P,
271 7
275 7 F275del,
302 9 A302V, A302E, A302T,
299 10
268 10 I268V, I268S,
278 10 Y278H,
235 10 I235N,
267 11 Y267C,
238 11 M238V, M238L, M238L,
300 11 A300T, A300S,
333 12
330 12
334 12 V334A,
265 13 T265I,
137 13 L137F, L137P,
329 13 A329T,
301 13
331 13
336 13 A336S,
281 13 Y281C
239 13
332 13
335 13 F335L, F335L, F335L,
307 14 V307L, V307L,
232 14
141 14 V141M,
236 14 L236Q, L236R,
296 14 F296S, F296L, F296L, F296L,
276 14 S276del,
134 14 L134P,
282 14 L282P,
318 14
298 15 S298I, S298N,
272 15 G272D, G272S, G272V,
328 15 I328del,
327 15 T327A, T327S, T327S,
338 15 S338F,
234 15 Q234H, Q234H,