SCN5A Variant S1700G Detail

We estimate the penetrance of LQTS for SCN5A S1700G around 3% and the Brugada syndrome penetrance around 17%. SCN5A S1700G was found in a total of 0 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. S1700G is not present in gnomAD. S1700G has been functionally characterized in 1 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 (1 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 S1700G around 3% (0/10) and the Brugada syndrome penetrance around 17% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.7 0.985 -0.41 0.924 17 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
29167113 2018 1 0 0 1 IBS
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 14 0 1 - -
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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
29167113 2018 HEK 75 -0.8 -7.2

S1700G has 76 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
1702 6
387 11
1304 15 T1304M,
1715 15
1687 13
388 14 I388S,
1698 5 A1698T,
1220 14 G1220E,
1673 9
1675 8
1666 13
1711 14 c.5131delG,
1707 10
1681 14 c.5040_5042delTTAinsC, Y1681F,
1694 5
1704 6 L1704H,
1226 10
1706 10 Q1706H,
1695 9 Q1695X,
1716 11 p.L1716SfsX71,
1688 11
1669 9
1671 10
1668 8 M1668T,
1676 7 M1676I, M1676T,
1692 9
386 14 G386R, G386E,
1219 15 S1219N,
1672 5 S1672Y,
1693 7
378 12
1699 5
331 12
1665 11
1712 14 G1712C, G1712S,
379 13
1680 11 A1680T, A1680P,
1703 5
1759 15 S1759C,
1719 15
1709 15 p.T1709del, T1709R, T1709M,
1701 5 M1701I,
1307 15
1228 13 Y1228H, Y1228C, Y1228F,
1690 13 c.5068_5070delGA, D1690N,
1678 12 N1678S,
1223 10 c.3667delG,
1755 12
1697 6
1222 14 p.L1222LfsX7, L1222R,
1227 12
1674 11 F1674V,
1713 14
390 11
394 14
1748 15 G1748D, p.G1748del,
1708 12 T1708I,
382 13
1696 6
1705 9
1689 13 D1689N,
1700 0
1717 15 L1717P,
1751 11
1677 11
1682 13
1752 12
1224 12
1670 11
1225 13 G1225K, E1225K,
375 15
1691 10
1720 14 c.5157delC,
1679 9
1667 12 V1667I,
1664 14