SCN5A Variant N1722I Detail

We estimate the penetrance of LQTS for SCN5A N1722I around 9% and the Brugada syndrome penetrance around 28%. SCN5A N1722I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. N1722I is not present in gnomAD. N1722I has been functionally characterized in 0 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 (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 N1722I around 9% (0/10) 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 0.81 37 8
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.

N1722I has 48 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 9 A1746T, A1746V,
1724 6
1741 12 D1741Y, D1741N, D1741E,
1406 14 G1406E, G1406R,
1715 14
1726 11
1745 5
1397 13 c.4189delT, c.4190delA,
1743 6 G1743E, G1743R,
1723 5 T1723N,
1725 7 P1725L,
1398 14 V1398M,
1407 13
1410 13
1747 10 V1747M,
1716 14 p.L1716SfsX71,
1714 14 D1714G,
1404 15
1744 6 S1744I,
1721 5
1742 8
1680 14 A1680T, A1680P,
1727 12
1719 9
1731 11
1728 8 C1728Y, C1728R, C1728W,
1678 14 N1678S,
1401 13
1399 9
1748 10 p.G1748del, G1748D,
1730 13 P1730H, P1730A, P1730L,
1683 11
1400 13 V1400I,
1718 9 S1718R,
1717 10 L1717P,
1751 15
1682 11
1750 13 L1750F,
1752 14
1722 0 N1722D,
1686 14
1749 10 I1749N,
1729 12 D1729N,
1740 13 G1740R,
1720 8 c.5157delC,
1732 13
1679 12
1685 12