SCN5A Variant c.4810+3_4810+6dupGGGT Detail

We estimate the penetrance of LQTS for SCN5A c.4810+3_4810+6dupGGGT around 3% and the Brugada syndrome penetrance around 45%. SCN5A c.4810+3_4810+6dupGGGT was found in a total of 2 carriers in 1 papers and/or in gnomAD: 2 had Brugada syndrome, 0 had LQTS. c.4810+3_4810+6dupGGGT is not present in gnomAD. c.4810+3_4810+6dupGGGT has been functionally characterized in 1 papers. This residue is located in a 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 (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 c.4810+3_4810+6dupGGGT around 3% (0/12) and the Brugada syndrome penetrance around 45% (5/12).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 46 1
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
15863661 2005 3 0 2 1 Conduction defects
LITERATURE, COHORT, AND GNOMAD: - 2 0 0 2 -
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.

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)
15863661 2005

c.4810+3_4810+6dupGGGT has 36 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
1600 7
1571 15 F1571C,
1606 7 T1606I,
1610 8 D1610G,
1569 14 A1569P,
1612 13
1615 13 Y1615X,
1572 13
1564 14
1596 12 F1596I, F1596C,
1605 4 c.4813+5insTGGG, G1605D, c.4813+2_4813+5dupTGGG, G1605C, c.4813+3_4813+6dupGGGT,
1611 11 I1611V,
1597 10 V1597M,
1616 7
1607 7
1599 9
1620 14 T1620K, T1620M,
1568 12
1617 6 p.F1617del,
1608 5
1565 13 L1565M,
1604 0 V1604M, c.4810+3_4810+6dupGGGT,
1602 6
1622 9
1618 10
1614 13
1626 13 R1626P, R1626L, R1626C, R1626H,
1601 5 L1601H,
1621 12
1609 8 S1609W, S1609L,
1603 5 I1603F,
1598 10 V1598A,
1623 14 R1623L, R1623Q, c.4867delC, R1623X,
1619 11 P1619L, c.4856delC, P1619Q,
1625 13
1613 10 Q1613L, Q1613H,