SCN5A Variant T824P Detail

We estimate the penetrance of LQTS for SCN5A T824P around 10% and the Brugada syndrome penetrance around 22%. SCN5A T824P was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T824P is not present in gnomAD. T824P has been functionally characterized in 0 papers. This residue is located in a Mild_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 (2 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 T824P around 10% (0/10) and the Brugada syndrome penetrance around 22% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.981 24 9
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 13 0 2 - -
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.

T824P has 41 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
821 9
1340 7 V1340I,
1339 7 L1339F, p.L1339del,
1461 14 T1461S,
1333 11
1344 12 F1344L, F1344S,
819 8
826 6 N826D,
818 11
825 4
781 14 W781X,
1464 13 L1464P, c.4389_4396delCCTCTTTA,
822 6 W822C, W822X,
944 12
830 11
833 15 G833R,
724 15 T724I,
1341 11
1334 13 I1334V,
1468 14 V1468F, V1468A,
831 11
820 11
823 4 P823T,
942 12
827 6
1460 14 F1460L,
816 13 F816L, F816Y,
1338 11 L1338V,
817 14 K817E,
815 14
1343 10
1337 9
1342 13
1332 13 P1332Q, P1332L,
1465 15 p.F1465_L1480dup,
1336 6
824 0
829 9
1335 11 M1335R,
832 12
828 7 L828V,