SCN5A Variant P1126L Detail

We estimate the penetrance of LQTS for SCN5A P1126L around 3% and the Brugada syndrome penetrance around 9%. SCN5A P1126L was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. P1126L is not present in gnomAD. P1126L has been functionally characterized in 0 papers. This residue is located in a Non_Hotspot region for Brugada syndrome and a Non_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (0 diagnosed with Brugada syndrome) and 5 individuals for LQTS (0 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A P1126L around 3% (0/10) and the Brugada syndrome penetrance around 9% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.579 5 0
PROVEAN scores less than -2 are considered deleterious. REVEL scores higher than 0.5 or 0.75 are considered likely pathogenic (higher sensitivity with the former cutoff, higher specificity with the latter cutoff). A PolyPhen-2 score of 0.85 or greater is considered likely pathogenic. BLAST-PSSM reflects the evolutionary conservation of residue substitutions, more negative numbers indicate fewer observations of the specific substitution than is expected. Penetrance Density is our previously published method to calculate the average BrS/LQTS probability density in a shell of residues surrounding a residue of interest (Kroncke et al. 2019).

Reported Carrier Data

PubMed ID Year Carriers Unaffected LQT3 BrS1 Other Other Disease
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
Summary totals might not agree with the literature table because of duplicate patients, which were excluded from the total counts. We do not distinguish here between multiple missense codons. Missense variants are combined across degenerate codon substitutions since codon-level data were not consistently available for curation.

P1126L has 31 previously observed neighbors within 15 angstroms

A residue within a folded protein on average has nearest neighbors that fall roughly into two shells: a "nearest" neighbor around 5-6 angstroms and a second shell around 11 angstroms. All variants shown in the rightmost column have been observed in at least one individual in the literature or gnomAD.

Neighbor Distance (Angstroms) Variants Observed in Individuals
1111 15
1112 14 Q1112X,
1113 14 A1113T, A1113V,
1114 13 D1114E, D1114N,
1115 13 W1115X, W1115R,
1116 12 R1116Q, R1116W,
1117 11
1118 11 Q1118X,
1119 10
1120 9
1121 8 A1121V,
1122 8
1123 7
1124 5
1125 4 A1125V, A1125G, A1125T,
1126 0
1127 4
1128 5 C1128X,
1129 7 G1129S,
1130 8 E1130K,
1131 8 T1131S, c.3391-1G>A, c.3390-1G>A, T1131I,
1132 9 P1132S,
1133 10
1134 11 D1134N, D1134E,
1135 11 S1135I,
1136 12 C1136Y,
1137 13
1138 13
1139 14
1140 14 S1140T,
1141 15