SCN5A Variant S1618Y Detail

We estimate the penetrance of LQTS for SCN5A S1618Y around 20% and the Brugada syndrome penetrance around 24%. SCN5A S1618Y was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. S1618Y is not present in gnomAD. S1618Y 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 (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 S1618Y around 20% (0/10) and the Brugada syndrome penetrance around 24% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.968 28 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 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.

S1618Y has 37 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
271 11 L271V,
270 12 Q270K,
1627 14
1624 10 V1624I,
388 14 I388S,
1602 11
1601 8 L1601H,
1609 13 S1609W, S1609L,
1608 13
1613 7 Q1613L, Q1613H,
1600 13
1615 10 Y1615X,
1612 12
1599 14
1545 15
1626 12 R1626C, R1626H, R1626L, R1626P,
267 15
1603 13 I1603F,
1625 10
1606 13 T1606I,
1610 10 D1610G,
272 15
1597 12 V1597M,
389 14 Y389H, Y389X,
1620 5 T1620K, T1620M,
1614 8
1619 4 P1619Q, P1619L, c.4856delC,
1605 10 c.4813+2_4813+5dupTGGG, c.4813+3_4813+6dupGGGT, G1605C, G1605D, c.4813+5insTGGG,
1611 13 I1611V,
1616 8
1617 4 p.F1617del,
1604 10 c.4810+3_4810+6dupGGGT, V1604M,
1622 7
1618 0
1621 5
1598 12 V1598A,
1623 8 R1623L, c.4867delC, R1623X, R1623Q,