SCN5A Variant L732P Detail

We estimate the penetrance of LQTS for SCN5A L732P around 20% and the Brugada syndrome penetrance around 30%. SCN5A L732P was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L732P is not present in gnomAD. L732P has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (3 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 L732P around 20% (0/10) and the Brugada syndrome penetrance around 30% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.958 40 23
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 12 0 3 - -
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.

L732P has 42 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
723 15 I723V,
811 13 R811H, c.2435_2436+3delTGGTAinsCGCCT, R811G,
733 5 F733L,
745 12
1406 14 G1406R, G1406E,
760 15 p.F760SfsX5,
812 13 L812Q,
1350 10 I1350T, I1350L,
755 14
731 4 T731I,
726 10
818 12
1353 13 V1353M,
737 10
1404 14
750 15 Q750R,
1349 13
749 10
1346 10 L1346I, L1346P,
724 12 T724I,
728 6 V728I,
727 9
735 5 A735V, A735T, A735E,
732 0
734 7 M734V, c.2201dupT,
756 11
814 12 R814Q,
1354 15
738 14
752 11 G752R,
1405 11 V1405M, V1405L,
815 11
1343 13
1342 13
725 11
751 14 V751I, V751F,
736 8 L736P,
730 7 N730K,
753 12
1347 13
729 5 p.L729del,
748 11 M748I,