SCN5A Variant F1956I Detail

We estimate the penetrance of LQTS for SCN5A F1956I around 4% and the Brugada syndrome penetrance around 6%. SCN5A F1956I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F1956I is not present in gnomAD. F1956I 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 F1956I around 4% (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 0.497 0 2
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.

F1956I 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
1941 15
1942 14 P1942S, P1942H,
1943 14
1944 13 R1944Q, R1944X,
1945 13
1946 12
1947 11
1948 11 I1948V,
1949 10 A1949S, A1949T,
1950 9 Y1950C,
1951 8 V1951L, V1951M,
1952 8
1953 7 p.S1953RfsX84,
1954 5 E1954K,
1955 4 N1955Y,
1956 0
1957 4 S1957P,
1958 5 R1958Q, R1958P, R1958X,
1959 7
1960 8
1961 8
1962 9 P1962L, P1962S,
1963 10 P1963L,
1964 11 S1964F,
1965 11 S1965N, S1965G,
1966 12
1967 13 p.S1967LfsX12,
1968 13 I1968N, I1968V, I1968M, I1968S, I1968T,
1969 14
1970 14 p.S1970_S1972del,
1971 15