SCN5A Variant F221L Detail

We estimate the penetrance of LQTS for SCN5A F221L around 13% and the Brugada syndrome penetrance around 21%. SCN5A F221L was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F221L is not present in gnomAD. F221L has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_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 F221L around 13% (0/10) and the Brugada syndrome penetrance around 21% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.901 24 13
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.

F221L has 47 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
223 7 V223L,
856 7 V856L,
862 15
859 9
198 15
195 11
228 15 K228R,
227 12 L227P,
197 13
216 9 S216L, S216X,
851 13 p.F851CfsX19, c.2550_2551dupGT, c.2552_2553dupGT, F851L,
221 0
196 10
852 10
854 12 c.2559delT,
222 8 R222X, R222L, R222Q,
224 6 L224F,
857 10 G857D,
849 14
226 12 A226G, A226V,
921 13
860 9 p.L860fsx89,
206 12
214 14
858 12 M858L,
144 14
217 5
918 12
855 10
917 14 L917V, L917R,
199 9 S199T,
148 13
204 10 A204T, c.611+3_611+4dupAA, A204V, c.611+1G>A,
203 7
202 11 I202T,
853 11
201 12
219 9 p.R219HfsX11, R219H, c.656_657insATTCA, R219C,
225 11 R225Q, R225W,
218 7
207 11
215 11 p.L215CfsX10,
914 12
200 7
145 15
861 12 c.2582_2583delTT, p.F861WfsX90,
220 4 T220I,