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Appendix e-1
e – METHODS
Phenotyping of study participants
In recent years authors have referred to typical Dravet Syndrome as “classical” and to atypical presentations as “borderline” Dravet Syndrome.e1,e2
Diagnostic criteria for classical Dravet syndrome (Dravet-C) were: seizure onset in the first year of life, mainly triggered by fever and often prolonged, later occurrence of various other seizure types (febrile and afebrile) including focal seizures, absences, tonic-clonic seizures; normal cognitive and motor development prior to seizure onset with subsequent slowing including plateauing or regression of skills. Status epilepticus is defined as an epileptic seizure lasting 30 minutes or longer with a prolonged seizure defined as lasting > 10 minutes. Consistent with previous reports we regarded the presence of myoclonic seizures and ataxia as highly characteristic for classical Dravet syndrome, however their absence did not exclude that diagnosis.e2
A diagnosis of borderline Dravet syndrome (Dravet-B) referred to patients who shared most of the features of classical Dravet syndrome, but had some atypical characteristics such as onset of seizures after 1 year, apparently only one seizure type such as generalized tonic clonic seizures (GTCS), or a normal developmental outcome.
Individuals were classified within the GEFS+ group if they had phenotypes consistent with febrile seizures plus (FS+) and a relevant family history.e3
Definition of functional domains and subunits
The functional domains in the SCN1A amino acid sequence were defined as per SWISS-PROT database.e4 The sodium channel α subunit folds into four homologous domains (I-IV), which are similar to one another and contain six α-helical transmembrane (S1-S6) segments.e5 We divided the entire protein into the following 14 subunits: N-terminal, S1 (segment 1), S1-S2 (segment 1-2 linker), S2, S2-S3, S3, S3-S4, S4, S4-S5, S5, S5-S6, S6, Linker regions (large intracellular loops linking the four homologous domains) and the C-terminal. As the 14 subunits comprise of different numbers of amino acids we calculated the frequency of mutations per amino acid in each subunit.
Physico-chemical properties of amino acids:
Hydropathy (HP): indicator of hydrophobicity – the larger the number, the more hydrophobic the amino acid.e6
Polarity (P) and Polar requirement (PR): indicators of side chain polarity – the larger the number, the more polar the amino acid.e7
Molecular volume (MV): indicator of side chain molecular volume.e8
Composition (C): atomic weight ratio of non-carbon over carbon elements in the amino acid side chain, reflecting composition differences between amino acids.e9
The value changes were calculated using the formula:e10
Value difference = A1 – A2
Absolute value change = ((A1 – A2) x (A1 – A2))1/2
A1: the physico-chemical index value of original amino acid residue
A2: the physico-chemical index value of mutated amino acid residue
Molecular analysis
Molecular analysis was performed on genomic DNA extracted from patients’ venous blood. All 26 exons of the SCN1A gene were amplified by PCR with 28 specific primer pairs and standard PCR conditions (primers available on request). PCR products were sequenced using ABI BigDye terminor sequencing kit. Sequence products were run on an ABI 3130 genetic analyzer (Applied Biosystems) and data were analysed using mutation surveyor software package (SoftGenetics V3.24). Where available, parental samples of the children found to have a SCN1A mutation, were tested by direct PCR amplification and DNA sequencing of the required exon to determine if the mutation had occurred de novo or was inherited.
Sequence changes were distinguished from single nucleotide polymorphisms and specific missense mutations were further validated by comparing them to a panel of anonymous DNA controls as control population.
In point mutation negative cases, when the phenotype suggested an SCN1A-related Epilepsy, multiplex ligation-dependent probe amplification (MLPA) was performed to detect large scale rearrangements of the gene. We used the commercially available MLPA kit from MRC-Holland (P137) and tests were conducted according to the manufacturer’s instructions. Electrophoresis of PCR products was performed using an ABI 3130 genetic analyzer and MLPA data were analysed using the GeneMarker software (SoftGenetics V1.8). The relative peak height of each exon was first normalised by dividing the average relative peak heights of the internal control probes. The normalised data for each peak was then quantified by dividing by the average relative peak height of the corresponding exons of the control samples.
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Table e-1: Mutations identified in the SCN1A gene in our laboratory
No / Exon/Intron / Protein
position / Sex / Phenotype / Mutation/
cDNA level / Mutation/
protein level / Mutation
class / Inheritance / Reference*
1 / 1 / N-terminal / M / Dravet-C / c.2T>C / p.Met1Thr / Missense / Unknown / Novel
2 / 1 / N-terminal / F / Dravet-C / c.49_51del3 / p. Phe17del / Inframe deletion / Unknown / Novel
3 / 1 / N-terminal / M / Dravet-C / c.67_68dupG / p.Ala24fsX4 / Frameshift / Unknown / Novel
4 / 1 / N-terminal / F / Dravet-C / c.76G>T / p.Glu26X / Nonsense / Unknown / Novel
5 / 1 / N-terminal / M / unclassified / c.133G>A / p.Asp45Asn / Missense / Unknown / Novel
6 / 1 / N-terminal / F / Dravet-C / c.172G>T / p.Gly58X / Nonsense / De novo / Novel
7 / 1 / N-terminal / M / Dravet-B / c.203T>C / p.Ile68Thr / Missense / Maternal / Novel
8 / 1 / N-terminal / F / Dravet-C / c.235G>A / p.Asp79Asn / Missense / De novo / Novel
9 / 1 / N-terminal / M / Dravet-B / c.249C>A / p.Tyr83X / Nonsense / De novo / Novel
10 / 1 / N-terminal / F / Dravet-C / c.251A>G / p.Tyr 84Cys / Missense / De novo / Previous reporte1
11 / Intron 1 / N-terminal / M / Dravet-C / c.264+3del4 / p.? / Splice / Unknown / Novel
12 / Intron 1 / N-terminal / M / GEFS+ / c.265-3C>T / p.? / Splice / Maternal / Novel
13 / 2 / N-terminal / M / Dravet-C / c.292G>C / p.Ala98Pro / Missense / De novo / Novel
14 / 2 / N-terminal / F / Dravet-C / c.301C>T / p.Arg101Trp / Missense / De novo / Previous reporte1
15 / 2 / N-terminal / F / Dravet-C / c.301C>T / p.Arg101Trp / Missense / De novo / Previous reporte1
16 / 2 / N-terminal / M / unclassified / c.301C>T / p.Arg101Trp / Missense / De novo / Previous reporte1
17 / 2 / N-terminal / M / Dravet-C / c.301C>T / p.Arg101Trp / Missense / Unknown / Previous reporte1
18 / 2 / N-terminal / M / Dravet-C / c.302G>A / p.Arg101Gln / Missense / De novo / Previous reporte11
19 / 2 / N-terminal / M / Dravet-C / c.302G>A / p.Arg101Gln / Missense / De novo / Previous reporte11
20 / 2 / N-terminal / F / Dravet-C / c.302G>A / p.Arg101Gln / Missense / Unknown / Previous reporte11
21 / 2 / N-terminal / F / Dravet-C / c.323T>G / p.Leu108Arg / Missense / Unknown / Novel
22 / 2 / N-terminal / M / Dravet-B / c.323T>G / p.Leu108Arg / Missense / Unknown / This study
23 / 2 / D1/S1 / M / Dravet-B / c.379C>G / p.His127Asp / Missense / De novo / Novel
24 / 2 / D1/S1 / F / FS+ / c.383C>A / p.Ser128X / Frameshift / Unknown / Previous reporte12
25 / 3 / D1S1 / M / Dravet-C / c.412_413delAT / p.Ile138PhefsX11 / Frameshift / Paternal / Novel
26 / 3 / D1/S1 / F / Dravet-C / c.429delGT / p.Phe144TyrfsX5 / Frameshift / Unknown / Previous reporte11
27 / 3 / D1/S1-S2 / M / Dravet-B / c.458G>A / p.Trp153X / Nonsense / Unknown / Novel
28 / Intron 3 / D1/S2 / F / Dravet-C / c.474-1G>A / p.? / Splice / De novo / Novel
29 / 4 / D1/S3 / M / Dravet-C / c.580G>C / p.Asp194Asn / Missense / Unknown / Novel
30 / 4 / D1/S3 / F / Dravet-C / c.596C>G / p.Thr199Arg / Missense / Unknown / Previous reporte1
31 / Intron 4 / D1/S3 / M / Dravet-C / c.602+1G>A / p.? / Splice / Unknown / Previous reporte13
32 / Intron 4 / D1/S3 / M / Dravet-C / c.602+1G>A / p.? / Splice / Unknown / Previous reporte13
33 / Intron 4 / D1/S3 / M / unclassified / c.602+1G>A / p.? / Splice / De novo / Previous reporte13
34 / Intron 4 / D1/S3 / F / Dravet-C / c.602+1G>A / p.? / Splice / Unknown / Previous reporte13
35 / Intron 4 / D1/S3 / F / Dravet-C / c.602+2T>A / p.? / Splice / Unknown / Novel
36 / 5 / D1/S4 / M / GEFS+ / c.652T>C / p.Phe218Leu / Missense / Maternal / Previous reporte14
37 / 5 / D1/S4 / F / Familial PS / c.652T>C / p.Phe218Leu / Missense / Paternal / Previous reporte14
38 / 5 / D1/S4 / M / Familial PS / c.652T>C / p.Phe218Leu / Missense / Paternal / Previous reporte14
39 / 5 / D1/S4 / M / Dravet-B / c.664C>T / p.Arg222X / Nonsense / De novo / Previous reporte15
40 / 5 / D1/S4 / M / Dravet-C / c.664C>T / p.Arg222X / Nonsense / Unknown / Previous reporte15
41 / 5 / D1/S4 / F / Dravet-C / c.664C>T / p.Arg222X / Nonsense / De novo / Previous reporte15
42 / 5 / D1/S4 / M / Dravet-C / c.680T>G / p.Ile227Ser / Missense / De novo / Previous reporte1
43 / 5 / D1/S4 / F / Dravet-C / c.680T>C / p.Ile227Thr / Missense / De novo / Novel
44 / 5 / D1/S4 / F / Dravet-C / c.680T>C / p.Ile227Thr / Missense / De novo / This study
45 / 5 / D1/S4 / F / Dravet-C / c.694G>A / p.Gly232Ser / Missense / Unknown / Previous reporte2
46 / 6 / D1/S4 / M / Dravet-C / c.698T>G / p.Leu233Arg / Missense / De novo / Novel
47 / 6 / D1/S5 / M / FS+ / c.761C>T / p.Thr254Ile / Missense / Unknown / Novel
48 / 6 / D1/S5 / F / Dravet-C / c.787delC / p.Lys263X / Nonsense / De novo / Novel
49 / 6 / D1/S5-S6 / M / Dravet-B / c.835C>T / p.Gln279X / Nonsense / De novo / Novel
50 / 6 / D1/S5-S6 / M / Dravet-B / c.835C>T / p.Gln279X / Nonsense / De novo / This study
51 / 6 / D1/S5-S6 / M / GEFS+ / c.871A>G / p.Ser291Gly / Missense / Unknown / Novel
52 / 6 / D1/S5-S6 / F / Dravet-C / c.893_894delTG / p.Val298GlufsX3 / Frameshift / Unknown / Novel
53 / 6 / D1/S5-S6 / M / MAE / c.940T>C / p.Trp314Arg / Missense / Maternal / Novel
54 / 7 / D1/S5-S6 / M / Dravet-B / c.992delT / p.Leu331fsX / Frameshift / De novo / Novel
55 / 7 / D1/S5-S6 / M / Dravet-C / c.1025C>T / p.Ala342Val / Missense / De novo / Novel
56 / 7 / D1/S5-S6 / M / Dravet-C / c.1028G>A / p.Gly343Asp / Missense / Unknown / Previous reporte13
57 / Intron 7 / D1/S5-S6 / F / Dravet-C / c.1028+1G>T / p.? / Splice / Unknown / Previous reporte1
58 / 8 / D1/S5-S6 / F / Dravet-C / c.1035T>A / p.Cys345X / Nonsense / De novo / Novel
59 / 8 / D1/S5-S6 / M / Dravet-C / c.1053T>G / p.Cys351Trp / Missense / De novo / Novel
60 / 8 / D1/S5-S6 / M / Dravet-C / c.1055_1056dupTG / p.Lys353fsX / Frameshift / De novo / Novel
61 / 8 / D1/S5-S6 / F / Dravet-C / c.1076A>G / p.Asn359Ser / Missense / De novo / Novel
62 / 8 / D1/S5-S6 / F / Dravet-C / c.1088C>G / p.Thr363Arg / Missense / Unknown / Novel
63 / 8 / D1/S5-S6 / F / Dravet-C / c.1090delA / p.Ser364AlafsX15 / Frameshift / De novo / Novel
64 / 8 / D1/S5-S6 / M / Dravet-C / c.1129C>T / p.Arg377X / Nonsense / Unknown / Previous reporte2
65 / 8 / D1/S5-S6 / F / unclassified / c.1144G>A / p.Asp382Asn / Missense / De novo / Novel
66 / 8 / D1/S5-S6 / F / Dravet-C / c.1150T>C / p.Trp384Arg / Missense / De novo / Novel
67 / 9 / D1/S5-S6 / F / Dravet-C / c.1176dupA / p.Arg393ThrfsX57 / Frameshift / Unknown / Novel
68 / 9 / D1/S5-S6 / F / Dravet-C / c.1177C>T / p.Arg393Cys / Missense / De novo / Previous reporte16
69 / 9 / D1/S5-S6 / M / Dravet-C / c.1178G>A / p.Arg393His / Missense / De novo / Previous reporte17
70 / 9 / D1/S6 / F / Dravet-C / c.1198A>G / p.Met400Val / Missense / Biparental / Novel
71 / 9 / D1/S6 / F / Dravet-C / c.1207T>G / p.Phe403Val / Missense / Unknown / Novel
72 / 9 / D1/S6 / M / Dravet-C / c.1216G>T / p.Val406Phe / Missense / Unknown / Novel
73 / 9 / D1/S6 / F / Dravet-C / c.1247delA / p.Asn416IlefsX2 / Frameshift / Unknown / Novel
74 / 9 / D1/S6 / F / Dravet-C / c.1258_1261del4 / p.Aln420TrpfsX27 / Frameshift / Unknown / Novel
75 / 9 / L1 / M / Dravet-C / c.1291C>T / p.Glu431X / Nonsense / Unknown / Novel
76 / 10 / L1 / M / Dravet-B / c.1378C>T / p.Gln460X / Nonsense / Unknown / Novel
77 / 10 / L1 / M / Dravet-C / c.1624C>T / p.Arg542X / Nonsense / Unknown / Previous reporte18
78 / 10 / L1 / M / Dravet-C / c.1639_1640dupAA / p.Tyr549GlyfsX10 / Frameshift / Unknown / Novel
79 / 11 / L1 / M / Dravet-C / c.1664_1667del4ins12 / p.Ser555PhefsX6 / Frameshift / De novo / Novel
80 / 11 / L1 / F / Dravet-C / c.1679_1686del8 / p.Arg560ProfsX8 / Frameshift / De novo / Novel
81 / 11 / L1 / F / Dravet-C / c.1687delC / p.Lys563TyrfsX622 / Frameshift / Unknown / Previous reporte1
82 / 11 / L1 / M / Dravet-C / c.1702C>T / p.Arg568X / Nonsense / Unknown / Previous reporte19
83 / 11 / L1 / M / Dravet-C / c.1702C>T / p.Arg568X / Nonsense / Unknown / Previous reporte19
84 / 11 / L1 / F / unclassified / c.1714_1718del5 / p.Thr572ProfsX5 / Frameshift / Unknown / Novel
85 / 11 / L1 / F / Dravet-C / c.1738C>T / p.Arg580X / Nonsense / Unknown / Previous reporte2
86 / 11 / L1 / F / Dravet-C / c.1837C>T / p.Arg613X / Nonsense / De novo / Previous reporte20
87 / 11 / L1 / M / Dravet-B / c.1876A>G / p.Ser626Gly / Missense / Unknown / Previous reporte1
88 / 12 / L1 / M / Dravet-B / c.2052delC / p.Thr685LeufsX5 / Frameshift / Unknown / Novel
89 / 12 / L1 / M / unclassified / c.2134C>T / p.Arg712X / Nonsense / De novo / Previous reporte19
90 / 12 / L1 / F / Dravet-C / c.2134C>T / p.Arg712X / Nonsense / Unknown / Previous reporte19
91 / 12 / L1 / M / Dravet-C / c.2134C>T / p.Arg712X / Nonsense / De novo / Previous reporte19
92 / 12 / L1 / M / Dravet-C / c.2134C>T / p.Arg712X / Nonsense / Unknown / Previous reporte19
93 / 12 / L1 / M / Dravet-C / c.2134C>T / p.Arg712X / Nonsense / Unknown / Previous reporte19
94 / 13 / L1 / F / Dravet-C / c.2284A>G / p.Asn762Asp / Missense / Paternal / Novel
95 / 13 / D2/S2 / M / Dravet-C / c.2354T>C / p.Met785Thr / Missense / De novo / Novel
96 / Intron 13 / D2/S2 / F / Dravet-C / c.2416-2G>A / p.? / Splice / De novo / Novel
97 / 14 / D2/S2 / F / Dravet-C / c.2421delC / p.Phe807LeufsX11 / Frameshift / De novo / Novel
98 / 14 / D2/S2 / F / Dravet-B / c.2435C>T / p.Thr812Ile / Missense / Unknown / Novel
99 / 14 / D2/S3 / F / Dravet-C / c.2505dupT / p.Asp836X / Nonsense / De novo / Novel
100 / 14 / D2/S3 / M / Dravet-C / c.2525T>G / p.Leu842Arg / Missense / Unknown / Novel
101 / 14 / D2/S3-S4 / M / Dravet-B / c.2560_2565del6 / p.Gly854_Leu855del / Inframe deletion / De novo / Novel
102 / 14 / D2/S4 / F / Dravet-C / c.2575C>T / p.Arg859Cys / Missense / Unknown / Previous reporte21
103 / 14 / D2/S4 / F / Dravet-C / c.2585G>A / p.Arg862Gln / Missense / De novo / Novel
104 / Intron 14 / D2/S4 / F / Dravet-C / c.2589+3A>T / p.? / Splice / De novo / Previous reporte1
105 / 15 / D2/S4 / F / Dravet-C / c.2591delT / p. Leu864ArgfsX13 / Frameshift / De novo / Novel
106 / 15 / D2/S4-S5 / M / Dravet-C / c.2665delG / p.Ala889LeufsX5 / Frameshift / De novo / Novel
107 / 15 / D2/S4-S5 / M / Dravet-C / c.2669T>C / p.Leu890Phe / Missense / De novo / Novel
108 / 15 / D2/S5-S6 / F / unclassified / c.2792G>A / p.Arg931His / Missense / Unknown / Novel
109 / 15 / D2/S5-S6 / F / Dravet-C / c.2796G>C / p.Trp932Cys / Missense / Unknown / Novel
110 / 15 / D2/S5-S6 / M / Dravet-C / c.2798A>C / p.His933Pro / Missense / Unknown / Novel
111 / 15 / D2/S5-S6 / M / unclassified / c.2824_2836del13 / p.Leu942AlafsX8 / Frameshift / De novo / Novel
112 / 15 / D2/S5-S6 / M / Dravet-C / c.2836C>T / p.Arg946Cys / Missense / De novo / Previous reporte11
113 / 15 / D2/S5-S6 / M / Dravet-C / C.2836C>T / p.Arg946Cys / Missense / De novo / Previous reporte11
114 / 15 / D2/S5-S6 / M / Dravet-C / c.2837G>A / p.Arg946His / Missense / De novo / Previous reporte11
115 / 15 / D2/S5-S6 / F / Dravet-C / c.2848G>C / p.Gly950Arg / Missense / De novo / Novel
116 / 15 / D2/S5-S6 / M / Dravet-B / c.2856G>A / p.Trp952X / Nonsense / Unknown / Novel
117 / 15 / D2/S5-S6 / M / Dravet-C / c.2860G>A / p.Glu954Lys / Missense / Unknown / Novel
118 / 15 / D2/S5-S6 / M / Dravet-C / c.2867T>A / p.Met956Lys / Missense / De novo / Novel
119 / 15 / D2/S5-S6 / M / Dravet-C / c.2870G>T / p.Trp957Leu / Missense / De novo / Previous reporte22
120 / 15 / D2/S5-S6 / M / Dravet-C / c.2872delG / p.Asp958ThrfsX16 / Frameshift / Unknown / Novel
121 / 15 / D2/S5-S6 / M / GEFS+ / c.2879T>C / p.Met960Thr / Missense / Unknown / Novel
122 / 15 / D2/S6 / M / Dravet-C / c.2908dupA / p.Thr970AsnfsX9 / Frameshift / De novo / Novel
123 / 15 / D2/S6 / M / GEFS+ / c.2917A>G / p.Met973Val / Missense / Unknown / Previous reporte1
124 / 15 / D2/S6 / F / Dravet-C / c.2928G>A / pMet976Ile / Missense / De novo / Novel
125 / 15 / D2/S6 / M / Dravet-B / c.2936G>T / p.Gly979Val / Missense / Unknown / Novel
126 / 16 / L2 / M / Dravet-B / c.2979C>G / p.Ser993Arg / Missense / Unknown / Novel
127 / 16 / L2 / M / Dravet-C / c.2995_2999del5ins8 / p.Asn999_Leu1000delins
LeuIleSer / Inframe indel / Unknown / Novel
128 / 16 / L2 / F / unclassified / c.3018T>G / p.Asp1006Glu / Missense / Maternal / Novel
129 / 16 / L2 / F / Dravet-C / c.3139G>T / p.Glu1047X / Nonsense / De novo / Novel
130 / Intron 16 / L2 / F / Dravet-C / c.3429+1G>T / p.? / Splice / Unknown / Novel
131 / 17 / L2 / M / Dravet-C / c.3448_3449delAG / p.Ser1150LeufsX5 / Frameshift / Unknown / Novel
132 / 17 / L2 / M / Dravet-C / c.3462delT / p.Gly1154fsX1163 / Frameshift / Unknown / Previous reporte1
133 / 17 / L2 / F / Dravet-C / c.3483_3489del7 / p.Pro1162LysfsX5 / Frameshift / Unknown / Novel
134 / 17 / L2 / M / Dravet-C / c.3539_3542del4 / p.Cys1180SerfsX27 / Frameshift / Unknown / Novel
135 / 18 / L2 / M / Dravet-C / c.3555T>A / p.Cys1185X / Nonsense / Unknown / Novel
136 / 18 / L2 / F / Dravet-B / c.3601G>T / p.Gly1201X / Nonsense / Unknown / Novel
137 / 18 / L2 / M / GEFS+ / c.3611G>C / p.Trp1204Ser / Missense / Unknown / Novel
138 / 18 / L2 / F / Dravet-B / c.3623G>A / p.Arg1208Lys / Missense / Maternal / Novel
139 / 18 / L2 / M / Dravet-C / c.3637C>T / p.Arg1213X / Nonsense / De novo / Previous reporte13
140 / 18 / D3/S1 / M / Dravet-C / c.3657G>A / p.Trp1219X / Nonsense / De novo / Novel
141 / 18 / D3/S1 / M / Dravet-C / c.3661G>A / p.Glu1221Lys / Missense / Unknown / Novel
142 / 18 / D3/S1 / M / unclassified / c.3669_3670dupA / p.Ile1224AsnfsX8 / Frameshift / Unknown / Novel
143 / 18 / D3/S1 / F / GEFS+ / c.3688C>T / p.Leu1230Phe / Missense / Maternal / Novel
144 / 18 / D3/S1 / M / Dravet-C / c.3688C>T / p.Leu1230Phe / Missense / Unknown / This study
145 / 19 / D3/S1-S2 / F / Dravet-C / c.3714A>C / p.Glu1238Asp / Missense / Unknown / Previous reporte1
146 / 19 / D3/S1-S2 / F / Dravet-C / c.3733C>T / p.Arg1245X / Nonsense / Unknown / Previous reporte12
147 / 19 / D3/S1-S2 / M / Dravet-C / c.3733C>T / p.Arg1245X / Nonsense / De novo / Previous reporte12
148 / 19 / D3/S2 / M / Dravet-C / c.3773_3775del3ins8 / p.Val1258_Phe1259delin
sAsp,Ser,LeufsX14 / Frameshift / Unknown / Novel
149 / 19 / D3/S2 / F / Dravet-C / c.3797A>C / p.Glu1266Ala / Missense / Unknown / Novel
150 / 19 / D3/S3 / M / Dravet-C / c.3862G>A / p.Asp1288Asn / Missense / De novo / Novel
151 / Intron 19 / D3/S3 / M / Dravet-C / c.3879+1G>T / p.? / Splice / De novo / Novel
152 / 20 / D3/S3-S4 / F / Dravet-C / c.3924A>T / p.Glu1308Asp / Missense / Maternal / Previous reporte2
153 / 20 / D3/S4 / M / Dravet-C / c.3829delG / p.Gly1310GlufsX9 / Frameshift / Unknown / Novel
154 / 20 / D3/S4 / F / Dravet-C / c.3931delG / p.Ala1311ProfsX8 / Frameshift / De novo / Novel
155 / 20 / D3/S4 / M / Dravet-B / c.3959C>T / p.Ala1320Val / Missense / De novo / Novel
156 / 20 / D3/S4 / F / Dravet-C / c.3968delC / p.Pro1323LeufsX2 / Frameshift / Unknown / Novel
157 / 20 / D3/S4 / M / Dravet-C / c.3976G>C / p.Ala1326Pro / Missense / Unknown / Previous reporte23
158 / 20 / D3/S4 / F / unclassified / c.3977C>A / p.Ala1326Asp / Missense / De novo / Novel
159 / 20 / D3/S4 / M / unclassified / c.3985C>T / p.Arg1329X / Nonsense / Unknown / Previous reporte2
160 / Intron 20 / D3/S4 / F / Dravet-B / c.4002+1G>A / p.? / Splice / Unknown / Novel
161 / Intron 20 / D3/S4 / F / Dravet-C / c.4002+2T>C / p.? / Splice / De novo / Novel
162 / 21 / D3/S4-S5 / F / Dravet-C / c.4049T>G / p.Val1350Gly / Missense / De novo / Novel
163 / 21 / D3/S5 / F / Dravet-C / c.4072T>C / p.Trp1358Arg / Missense / De novo / Novel
164 / 21 / D3/S5 / F / Dravet-C / c.4073G>A / p.Trp1358X / Nonsense / De novo / Novel
165 / 21 / D3/S5 / M / Dravet-B / c.4108G>C / p.Ala1370Pro / Missense / Unknown / Novel
166 / 21 / D3/S5-S6 / F / Dravet-C / c.4132A>C / p.Asn1378His / Missense / Unknown / Novel
167 / 21 / D3/S5-S6 / F / Dravet-C / c.4133A>C / p.Asn1378Thr / Missense / Unknown / Novel
168 / 21 / D3/S5-S6 / M / Dravet-C / c.4181C>T / p.Thr1394Ile / Missense / De novo / Novel
169 / 21 / D3/S5-S6 / F / Dravet-C / c.4187G>A / p.Cys1396Tyr / Missense / De novo / Novel
170 / 21 / D3/S5-S6 / M / Dravet-C / c.4205_4208del4 / p.Arg1402MetfsX9 / Frameshift / De novo / Novel
171 / 21 / D3/S5-S6 / M / GEFS+ / c.4240A>G / p.Asn1414Asp / Missense / Paternal / Novel
172 / 21 / D3/S5-S6 / M / Dravet-C / c.4250A>G / p.Asn1417Ser / Missense / De novo / Novel
173 / 21 / D3/S5-S6 / M / Dravet-C / c.4267C>T / p.Leu1423Phe / Missense / Maternal / Novel
174 / Intron 21 / D3/S5-S6 / F / Dravet-C / c.4284+1G>T / p.? / Splice / De novo / Novel
175 / 22 / D3/S5-S6 / M / Dravet-C / c.4285delGCC / p.Ala1429del / Inframe deletion / De novo / Novel
176 / 22 / D3/S5-S6 / F / Dravet-C / c.4298G>T / p.Gly1433Val / Missense / Paternal / Novel
177 / Intron 22 / D3/S5-S6 / M / Dravet-C / c.4339-12C>A / p.? / Splice / De novo / Novel
178 / 23 / D3/S5-S6 / F / Dravet-C / c.4348C>A / p.Gln1450Lys / Missense / De novo / Novel
179 / 23 / D3/S5-S6 / M / Dravet-C / c.4351C>T / p.Pro1451Ser / Missense / De novo / Novel
180 / 2 & 23 / 1: D1/S1 / F / Dravet-C / c.379C>G / p.His127Asp / Missense / Unknown / This study
2: D3/S5-S6 / c.4351C>T / p.Pro1451Ser / Missense / Unknown / This study
181 / 23 / D3/S5-S6 / M / Dravet-C / c.4360G>A / p.Glu1454Lys / Missense / De novo / Novel
182 / 23 / D3/S6 / F / Dravet-C / c.4384T>C / p.Tyr1462His / Missense / De novo / Novel
183 / 23 / D3/S6 / M / Dravet-B / c.4384T>C / p.Tyr1462His / Missense / De novo / This study
184 / 23 / D3/S6 / M / Dravet-B / c.4428C>A / p.Asn1476Lys / Missense / De novo / Novel
185 / 23 / D3/S6 / F / unclassified / C.4449A>G / p.Ile1483Met / Missense / De novo / Novel
186 / 23 / L3 / F / Dravet-C / c.4471A>T / p.Lys1491X / Nonsense / Unknown / Novel
187 / Intron 23 / L3 / F / Dravet-C / c.4476+1A>G / p.? / Splice / Unknown / Novel
188 / Intron 23 / L3 / M / Dravet-C / c.4476+1A>G / p.? / Splice / Unknown / This study
189 / 24 / D3S6 / F / Dravet-C / c.4497delT / p.Phe1499LeufsX2 / Frameshift / Unknown / Novel
190 / 24 / L3 / M / Dravet-B / c.4507G>A / p.Glu1503Lys / Missense / Unknown / Novel
191 / 24 / L3 / M / Dravet-C / c.4524T>A / p.Tyr1508X / Nonsense / Unknown / Novel
192 / 24 / L3 / F / Dravet-C / c.4547C>A / p.Ser1516X / Nonsense / Paternal / Previous reporte24
193 / 24 / L3 / F / Dravet-C / c.4547C>A / p.Ser1516X / Nonsense / Paternal / Previous reporte24
194 / 24 / L3 / M / Dravet-C / c.4554dupA / p.Pro1519ThrfsX21 / Frameshift / Unknown / Previous reporte22
195 / 24 / L3 / M / Dravet-C / c.4573C>T / p.Arg1525X / Nonsense / Unknown / Previous reporte20
196 / 24 / L3 / M / Dravet-B / c.4573C>T / p.Arg1525X / Nonsense / De novo / Previous reporte20
197 / 24 / L3 / F / Dravet-C / c.4573C>T / p.Arg1525X / Nonsense / De novo / Previous reporte20
198 / 24 / L3 / F / Dravet-C / c.4577delC / p.Pro1526GlnfsX13 / Frameshift / Unknown / Novel
199 / Intron 24 / L3 / M / Dravet-C / c.4581+3A>T / p.? / Splice / Unknown / Novel
200 / Intron 24 / L3 / F / unclassified / c.4581+3A>T / p.? / Splice / Paternal / This study
201 / Intron 24 / L3 / M / Dravet-C / c.4582-2A>T / p.? / Splice / De novo / Novel
202 / 25 / D4/S1 / M / Dravet-C / c.4631A>G / p.Asp1544Gly / Missense / De novo / Novel
203 / 25 / D4/S1 / M / Dravet-C / c.4657_4668del11 / p.Leu1553HisfsX8 / Frameshift / De novo / Novel
204 / 25 / D4/S2 / F / Dravet-C / c.4757G>A / p.Gly1586Glu / Missense / Unknown / Previous reporte2
205 / 25 / D4/S2 / F / Dravet-C / c.4762T>C / p.Cys1588Arg / Missense / Unknown / Previous reporte22
206 / 25 / D4/S2 / F / Dravet-C / c.4775T>C / Leu1592Pro / Missense / Unknown / Novel
207 / 25 / D4/S2 / M / Dravet-B / c.4775T>A / p.Leu1592His / Missense / Unknown / Novel
208 / 25 / D4/S2-S3 / M / GEFS+ / c.4787G>A / p.Arg1596His / Missense / Paternal / Novel
209 / 25 / D4/S3 / F / Dravet-B / c.4814A>G / p.Asn1605Ser / Missense / De novo / Novel
210 / 25 / D4/S3 / M / Dravet-C / c.4841delT / p.Leu1614ProfsX4 / Frameshift / De novo / Novel
211 / Intron 25 / D4/S3 / F / Dravet-C / c.4852+2T>C / p.? / Splice / Unknown / Novel
212 / Intron 25 / D4/S3 / F / Dravet-C / c.4853-2A>T / p.? / Splice / Unknown / Novel
213 / 26 / D4/S4 / M / Dravet-B / c.4906C>T / p.Arg1636X / Nonsense / Unknown / Novel
214 / 26 / D4/S4 / F / Dravet-C / c.4910T>A / p.Val1637Glu / Missense / Unknown / Novel
215 / 26 / D4/S4 / M / Dravet-C / c.4913T>C / p.Ile1638Thr / Missense / De novo / Novel
216 / 26 / D4/S4 / M / unclassified / c.4913T>C / p.Ile1638Thr / Missense / De novo / This study
217 / 26 / D4/S4 / M / Dravet-C / c.4933C>T / p.Arg1645X / Nonsense / Unknown / Previous reporte11
218 / 26 / D4/S4 / F / Dravet-C / c.4942C>T / p.Arg1648Cys / Missense / Unknown / Previous reporte19
219 / 26 / D4/S4 / M / Dravet-C / c.4942C>T / p.Arg1648Cys / Missense / Unknown / Previous reporte19
220 / 26 / D4/S4 / F / Dravet-B / c.4958C>A / p.Ala1653Glu / Missense / Unknown / Novel
221 / 26 / D4/S4-S5 / F / Dravet-C / c.4979T>C / p.Leu1660Pro / Missense / Unknown / Novel
222 / 26 / D4/S4-S5 / F / Dravet-C / c.4989delGinsCC / p.Leu1663PhefsX10 / Frameshift / De novo / Novel
223 / 26 / D4/S4-S5 / F / Dravet-C / c.5000T>C / p.Leu1667Pro / Missense / De novo / Novel
224 / 26 / D4/S4-S5 / M / Dravet-B / c.5003C>T / p.Pro1668Leu / Missense / Unknown / Novel
225 / 26 / D4/S4-S5 / M / Dravet-C / c.5015A>T / p.Asn1672Ile / Missense / Unknown / Novel
226 / 26 / D4/S5 / M / Dravet-C / c.5018T>C / p.Ile1673Thr / Missense / Unknown / Novel
227 / 26 / D4/S5 / F / unclassified / c.5047A>T / p.Ile1683Phe / Missense / Maternal / Novel
228 / 26 / D4/S5 / M / Dravet-C / c.5048T>C / p.Ile1683Thr / Missense / Unknown / Novel
229 / 26 / D4/S5 / M / Dravet-C / c.5050T>G / p.Tyr1684Asp / Missense / Unknown / Novel
230 / 26 / D4/S5 / M / Dravet-B / c.5052C>A / p.Tyr1684X / Nonsense / De novo / Novel
231 / 26 / D4/S5 / M / Dravet-C / c.5062G>T / p.Gly1688Trp / Missense / Unknown / Novel
232 / 26 / D4/S5 / F / Dravet-C / c.5081_5082dupAT / p.Tyr1694TyrfsX22 / Frameshift / De novo / Novel
233 / 26 / D4/S5-S6 / F / Dravet-C / c.5100dupG / p.Ile1701AspfsX3 / Frameshift / De novo / Novel
234 / 26 / D4/S5-S6 / M / Dravet-C / c.5141T>G / p.Met1714Arg / Missense / Unknown / Previous reporte16
235 / 26 / D4/S5-S6 / M / Dravet-C / c.5178G>A / p.Trp1726X / Nonsense / Unknown / Novel
236 / 26 / D4/S5-S6 / F / GEFS+ / c.5216C>T / p.Pro1739Leu / Missense / Paternal / Novel
237 / 26 / D4/S5-S6 / M / FS+ / c.5216C>T / p.Pro1739Leu / Missense / Unknown / This study
238 / 26 / D4/S6 / M / Dravet-C / c.5288T>A / p.Ile1763Asn / Missense / De novo / Novel
239 / 26 / D4/S6 / M / Dravet-C / c.5308A>T / p.Ile1770Phe / Missense / Unknown / Novel
240 / 26 / D4/S6 / M / Dravet-C / c.5309T>A / p.Ile1770Asn / Missense / Unknown / Novel
241 / 26 / D4/S6 / F / Dravet-B / c.5309T>C / p.Ile1770Thr / Missense / Unknown / Novel
242 / 26 / D4/S6 / M / Dravet-C / c.5339T>C / p.Met1780Thr / Missense / Unknown / Previous reporte12
243 / 26 / D4/S6 / F / Dravet-C / c.5348C>T / p.Ala1783Val / Missense / De novo / Previous reporte22
244 / 26 / C-terminal / M / Dravet-C / c.5359G>A / p.Glu1787Lys / Missense / Unknown / Previous reporte22
245 / 26 / C-terminal / M / Dravet-C / c.5488C>T / p.Gln1830X / Nonsense / De novo / Novel
246 / 26 / C-terminal / M / Dravet-C / c.5494G>C / p.Ala1832Pro / Missense / Unknown / Novel
247 / 26 / C-terminal / M / Dravet-C / c.5536_5339del4 / p.Lys1846SerfsX11 / Frameshift / Unknown / Previous reporte15
248 / 26 / C-terminal / M / Dravet-C / c.5555T>A / p.Met1852Lys / Missense / Unknown / Novel
249 / 26 / C-terminal / F / Dravet-C / c.5564C>T / p.Pro1855Leu / Missense / De novo / Novel
250 / 26 / C-terminal / M / GEFS+ / c.5600T>C / p.Ile1867Thr / Missense / Unknown / Previous reporte25
251 / 26 / C-terminal / M / Dravet-C / c.5629dupT / p.Asp1544X / Nonsense / Unknown / Novel
252 / 26 / C-terminal / F / Dravet-C / c.5639G>A / p.Gly1880Glu / Missense / Unknown / Novel
253 / 26 / C-terminal / M / Dravet-C / c.5674C>T / p.Arg1892X / Nonsense / Unknown / Previous reporte24
254 / 26 / C-terminal / M / Dravet-C / c.5725_5727del3 / p.Thr1909del / Inframe deletion / De novo / Novel
255 / 26 / C-terminal / F / Dravet-C / c.5733_5734delAC / p.Arg1912LysfsX32 / Frameshift / De novo / Novel
256 / 26 / C-terminal / F / Dravet-C / c.5778C>G / p.Tyr1926X / Nonsense / Unknown / Novel
257 / 26 / C-terminal / M / Dravet-C / c.5780_5781del2ins8 / p.Arg1927delinsIle,Ile,Gln / Inframe indel / De novo / Novel
258 / 26 / C-terminal / M / Dravet-B / c.5788delC / p.Leu1930PhefsX2 / Frameshift / De novo / Novel
259 / 1 / NA / M / Dravet-C / Deletion exon 1 / No protein synthesis / Gross
rearrangement / Unknown / Novel
260 / 21 / NA / M / Dravet-C / Deletion exon 21 / No protein synthesis / Gross
rearrangement / De novo / Previous reporte27
261 / 1-16 / NA / M / Dravet-C / Deletion exons 1-16 / No protein synthesis / Gross
rearrangement / Unknown / Previous reporte2
262 / 17+18 / NA / F / Dravet-C / Deletion exons 17&18 / No protein synthesis / Gross
rearrangement / Unknown / Novel
263 / 17-26 / NA / F / Dravet-C / Deletion exons 17-26 / No protein synthesis / Gross
rearrangement / Unknown / Previous reporte28
264 / 17-26 / NA / F / Dravet-C / Deletion exons 17-26 / No protein synthesis / Gross
rearrangement / De novo / Previous reporte28
265 / 17-26 / NA / M / Dravet-C / Deletion exons 17-26 / No protein synthesis / Gross
rearrangement / De novo / Previous reporte28
266 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
267 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
268 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
269 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
270 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
271 / 1-26 / NA / M / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / De novo / Previous reporte22
272 / 1-26 / NA / F / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / Unknown / Previous reporte22
273 / 1-26 / NA / F / Dravet-C / Whole gene deletion / No protein synthesis / Gross
rearrangement / Unknown / Previous reporte22
*References refer to first description of the mutation in another cohort
1
E-Zuberi
Table e-2: Missense polymorphisms identified in the SCN1A gene
Exon / cDNA position / Predicted protein change / Protein domain / Grantham score / Reference7 / c.998C>T / p.Ala333Val / D1S5-6 / 64 / This study
11 / c.1811G>A / p.Arg604His / L1 / 29 / Previous reporte29
12 / c.2095G>A / p.Val699Ile / L1 / 29 / Previous reporte29
15 / c.2770G>A / p.Ala924Thr / D2S5-6 / 58 / Previous reporte2
16 / c.3199A>G / p.Thr1067Ala / L2 / 58 / Previous reporte26
16 / c.3235G>A / p.Val1079Ile / L2 / 29 / Previous reporte2
16 / c.3325C>A / p.Pro1109Thr / L2 / 38 / Previous reporte2
17 / c.3481G>A / p.Ala1161Thr / L2 / 58 / Previous reporte29
25 / c.4712C>G / p.Thr1571Ser / D4S1-2 / 58 / This study
26 / c.5782C>G / p.Arg1928Gly / C-terminal / 125 / Previous reporte26
26 / c.5864T>C / p.Ile1955Thr / C-terminal / 89 / Previous reporte30
Abbreviations: D = domain; S = segment; L = linker
Table e-3: Missense changes of human SCN1A protein compared to orthologs of chimpanzee (Pan troglodytes) and rat (Rattus norvegicus)
Exon / Predicted protein change / Protein domain / Grantham score / Species6 / p.Ile278Val / D1S5-6 / 29 / Rat
6 / p.Ile296Val / D1S5-6 / 29 / Rat
6 / p.Val298Thr / D1S5-6 / 69 / Rat
6 / p.Asn299Asp / D1S5-6 / 23 / Rat
6 / p.Ile305Val / D1S5-6 / 29 / Rat
7 / p.Phe330Val / D1S5-6 / 50 / Rat
9 / p.Ile448Leu / L1 / 5 / Rat
10 / p.Thr463Ala / L1 / 58 / Rat
10 / p.Glu517Asp / L1 / 45 / Rat
10 / p.Gln521His / L1 / 24 / Rat
11 / p.Val634Gly / L1 / 109 / Rat
11 / p.Phe635Leu / L1 / 22 / Rat
13 / p.Val760Ile / L1 / 29 / Rat
13 / p.Asp794Glu / D2S1-2 / 45 / Rat
13 / p.Asn798His / D2S1-2 / 68 / Rat
15 / p.Gln928Lys / D2S5-6 / 53 / Rat
15 / p.Gly979Arg / D2S6 / 125 / Rat
16 / p.Ile1039Val / L2 / 29 / Rat
16 / p.Lys1057Arg / L2 / 26 / Rat
16 / p.Ser1060Asn / L2 / 46 / Rat
16 / p.Met1062Thr / L2 / 81 / Rat
16 / p.Tyr1075Cys / L2 / 194 / Rat
17 / p.Val1163Ala / L2 / 64 / Chimpanzee & Rat
17 / p.Val1169Met / L2 / 21 / Rat
18 / p.Asn1195Ser / L2 / 46 / Rat
21 / p.Ile1377Val / D3S5 / 29 / Rat
21 / p.Arg1384Thr / D3S5-6 / 71 / Rat
21 / p.Asp1386Glu / D3S5-6 / 45 / Rat
21 / p.Glu1388Thr / D3S5-6 / 65 / Rat
21 / p.Asp1389Glu / D3S5-6 / 45 / Rat
21 / p.Thr1394Ser / D3S5-6 / 58 / Rat
25 / p.Glu1567Asp / D4S1-2 / 45 / Rat
25 / p.Thr1571Ser / D4S1-2 / 58 / Rat
26 / p.Ile1947Leu / C-terminal / 5 / Rat
26 / p.Ile1955Val / C-terminal / 29 / Rat
Abbreviations: D = domain; S = segment; L = linker
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