SCN5A Variant A149T Detail

We estimate the penetrance of LQTS for SCN5A A149T around 2% and the Brugada syndrome penetrance around 10%. SCN5A A149T was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A149T is not present in gnomAD. A149T 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 A149T around 2% (0/10) and the Brugada syndrome penetrance around 10% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.503 7 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.

A149T has 49 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
888 12
154 10 P154L,
848 14 I848F,
223 12 V223L,
856 13 V856L,
862 15
859 12
1447 14
1444 14 L1444I,
153 8
149 0
147 7
164 14 F164L,
887 11
143 10
142 12
156 11 W156R, W156X,
886 13 H886P, H886Q,
851 9 c.2552_2553dupGT, F851L, c.2550_2551dupGT, p.F851CfsX19,
222 13 R222L, R222X, R222Q,
852 13
854 10 c.2559delT,
155 11
857 13 G857D,
150 4
157 12 T157I,
882 12
160 13 p.V160fs,
881 14
226 13 A226G, A226V,
889 15
858 9 M858L,
144 9
855 9
148 5
884 6
885 9
146 5 V146M, V146A,
847 15
152 6 D152N,
141 13 I141V, I141N,
161 13 E161Q, E161K,
219 13 R219H, c.656_657insATTCA, R219C, p.R219HfsX11,
151 5
883 9
850 14 c.2549_2550insTG, V850M,
145 7
140 15
220 15 T220I,