SCN5A Variant I167S Detail

We estimate the penetrance of LQTS for SCN5A I167S around 4% and the Brugada syndrome penetrance around 19%. SCN5A I167S was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I167S is not present in gnomAD. I167S 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 (1 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 I167S around 4% (0/10) and the Brugada syndrome penetrance around 19% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.98 18 0
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 14 0 1 - -
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.

I167S has 45 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
198 13
147 14
164 6 F164L,
170 6 F170I,
228 14 K228R,
138 11 M138I,
171 7
143 11
137 7 I137V,
142 13
197 12
163 6 c.486delC,
169 6
222 13 R222Q, R222L, R222X,
127 13
174 11 V174I,
133 10
132 13 c.393-5C>A,
160 10 p.V160fs,
134 12 N134S,
205 13 Y205X, c.612-2A>G,
166 4 A166T,
144 11
172 9
139 11 p.I137_C139dup,
165 6
204 12 c.611+1G>A, A204V, A204T, c.611+3_611+4dupAA,
162 11 Y162H, Y162C,
208 13 E208K,
136 9 L136P,
168 5
202 14 I202T,
175 12 K175N,
141 10 I141N, I141V,
135 14 M135V,
167 0
128 13 c.381dupT,
161 11 E161K, E161Q,
201 10
225 11 R225Q, R225W,
159 13 Y159C, Y159X,
173 11
200 13
145 15
140 7