SCN5A Variant G1748R Detail

We estimate the penetrance of LQTS for SCN5A G1748R around 34% and the Brugada syndrome penetrance around 28%. SCN5A G1748R was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. G1748R is not present in gnomAD. G1748R has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a 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 (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A G1748R around 34% (1/10) and the Brugada syndrome penetrance around 28% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.986 34 44
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 1 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.

G1748R has 58 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
1746 5 A1746T, A1746V,
1724 15
1406 13 G1406E, G1406R,
1757 14
1715 12
1687 15
1745 6
1756 11 I1756V,
1675 10
1743 9 G1743R, G1743E,
1723 13 T1723N,
1754 9
1707 12
1694 11
1411 14
1407 14
1704 13 L1704H,
1410 10
1747 4 V1747M,
1716 10 p.L1716SfsX71,
1714 12 D1714G,
1688 14
1671 11
1676 14 M1676T, M1676I,
1744 6 S1744I,
1721 6
1753 7 T1753A,
1672 14 S1672Y,
1742 13
1712 14 G1712S, G1712C,
1680 13 A1680T, A1680P,
1703 14
1719 10
1758 15 p.I1758del, I1758V,
1678 9 N1678S,
1755 11
1674 10 F1674V,
1399 14
1713 11
1748 0 p.G1748del, G1748D,
1683 15
1409 14 Y1409C, Y1409X,
1400 14 V1400I,
1718 10 S1718R,
1700 15
1717 7 L1717P,
1751 5
1677 12
1682 12
1750 5 L1750F,
1752 5
1722 10 N1722D,
1749 4 I1749N,
1720 6 c.5157delC,
1679 8
1685 14
1414 13 Q1414H,
1413 13