SCN5A Variant H1997N Detail

We estimate the penetrance of LQTS for SCN5A H1997N around 2% and the Brugada syndrome penetrance around 6%. SCN5A H1997N was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. H1997N is not present in gnomAD. H1997N has been functionally characterized in 0 papers. This residue is located in a Non_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 (0 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 H1997N around 2% (0/10) and the Brugada syndrome penetrance around 6% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.32 1 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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
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.

H1997N has 31 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
1982 15 R1982T,
1983 14 A1983V, A1983G,
1984 14 T1984I,
1985 13 S1985R,
1986 13 D1986G, D1986N,
1987 12 N1987K,
1988 11 L1988R,
1989 11
1990 10 V1990L,
1991 9 R1991Q, R1991W,
1992 8 G1992A,
1993 8
1994 7
1995 5 Y1995X,
1996 4 S1996N, S1996R,
1997 0 H1997R,
1998 4
1999 5
2000 7 D2000Y,
2001 8
2002 8 A2002T,
2003 9 D2003N,
2004 10 p.F2004dup, F2004V, F2004L, F2004I,
2005 11 P2005L, P2005A, P2005S,
2006 11 p.P2006LfsX32, P2006A, P2006T, p.Pro2006del,
2007 12 p.S2007FfsX7,
2008 13 P2008L,
2009 13 D2009E,
2010 14 R2010G,
2011 14
2012 15 R2012H, R2012C,