KCNQ1 Variant L203P

Summary of observed carriers, functional annotations, and structural context for KCNQ1 L203P. Data combine curated literature, international cohorts, and gnomAD observations.

Estimated LQT1 penetrance

70%

7/11 effective observations

Total carriers

1

1 LQT1 · 0 unaffected

Functional studies

0

Publications with functional data

L203P 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 (%)
-6.05 1.0 -4 0.971 74

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
21459285 2011 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 L203P.
Neighbour residue Distance (Å) Observed variants
203 0 L203P,
204 5 I204M, I204F,
206 5 V206L,
202 5 D202N, D202H,
207 6 V207M, V207L, V207L, V207L, V207L, V207del
171 6
200 6
205 6 V205M,
199 7 S199A,
201 7 I201del,
194 8 A194P, A194T,
168 9 G168R, G168R, G168R, G168R,
208 9 A208V,
209 10 S209P,
198 10 I198V, I198T,
210 10 M210I, M210I, M210I,
167 10
175 10 L175I,
172 10 V172M, V172E,
240 11 H240R, H240P,
164 11
197 11 P197L,
233 11 L233P,
174 11 R174H, R174C, R174L,
193 11 F193L, F193L, F193L,
170 11
236 12 L236Q, L236R,
237 12
196 12
169 12 T169M, T169R,
211 12
195 12 R195Q, R195W,
191 12
165 13 V165M,
239 13
173 14
243 14 R243H, R243C, R243P, R243S,
166 14 F166V,
190 14 R190W, R190Q, R190L,
212 14
232 14
163 14
176 15
213 15