SCN5A Variant Y168F Detail

We estimate the penetrance of LQTS for SCN5A Y168F around 12% and the Brugada syndrome penetrance around 17%. SCN5A Y168F was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. Y168F is not present in gnomAD. Y168F has been functionally characterized in 1 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 Y168F around 12% (0/10) and the Brugada syndrome penetrance around 17% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.85 0.951 8.42 0.892 19 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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
25483584 2014 HEK 50 11 2

Y168F has 59 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 13 V223L,
198 10
147 13
164 6 F164L,
195 15
170 9 F170I,
228 11 K228R,
138 10 M138I,
227 14 L227P,
171 6
143 11
137 7 I137V,
142 12
197 8
229 14
163 9 c.486delC,
196 12
169 6
222 10 R222L, R222X, R222Q,
224 13 L224F,
174 12 V174I,
133 11
160 11 p.V160fs,
134 12 N134S,
226 12 A226G, A226V,
205 11 Y205X, c.612-2A>G,
206 14
166 6 A166T,
144 9
172 8
199 11 S199T,
139 11 p.I137_C139dup,
148 13
165 5
204 9 c.611+1G>A, c.611+3_611+4dupAA, A204V, A204T,
162 11 Y162H, Y162C,
203 12
208 12 E208K,
136 11 L136P,
168 0
175 11 K175N,
202 11 I202T,
194 13
141 8 I141V, I141N,
135 14 M135V,
167 5
128 14 c.381dupT,
161 10 E161Q, E161K,
201 6
219 15 R219H, c.656_657insATTCA, R219C, p.R219HfsX11,
225 7 R225Q, R225W,
218 15
159 15 Y159C, Y159X,
176 14
207 13
173 11
200 9
140 7
145 13