# 619317

DEVELOPMENTAL AND EPILEPTIC ENCEPHALOPATHY 6B; DEE6B


Phenotype-Gene Relationships

Location Phenotype Phenotype
MIM number
Inheritance Phenotype
mapping key
Gene/Locus Gene/Locus
MIM number
2q24.3 Developmental and epileptic encephalopathy 6B, non-Dravet 619317 AD 3 SCN1A 182389
Clinical Synopsis
 
Phenotypic Series
 

INHERITANCE
- Autosomal dominant
HEAD & NECK
Head
- Microcephaly (in some patients)
Face
- Dysmorphic facial features, nonspecific (in some patients)
- Orofacial dyskinesia
Eyes
- Hypertelorism
- Poor eye contact
- Nystagmus
ABDOMEN
Gastrointestinal
- Tube feeding
SKELETAL
Spine
- Scoliosis
NEUROLOGIC
Central Nervous System
- Epileptic encephalopathy
- Global developmental delay, profound
- Early normal development until seizure onset
- Inability to walk
- Absent speech
- Impaired intellectual development, profound
- Seizures, multiple types
- Generalized tonic-clonic seizures
- Myoclonic seizures
- Tonic seizures
- Generalized spike wave discharges seen on EEG
- Multifocal discharges
- Status epilepticus
- Hypotonia, axial
- Peripheral hypertonia
- Hyperkinetic movement disorder
- Choreoathetosis
- Dystonia
- Myoclonus
- Cerebral atrophy seen on brain imaging
- Small hippocampus
- Dysmorphic corpus callosum
- White matter abnormalities
MISCELLANEOUS
- Onset of seizures in early infancy (6 to 12 weeks)
- Seizures are usually intractable
- De novo mutation
MOLECULAR BASIS
- Caused by mutation in the sodium voltage-gated channel, alpha subunit 1 gene (SCN1A, 182389.0025)
Developmental and epileptic encephalopathy - PS308350 - 114 Entries
Location Phenotype Inheritance Phenotype
mapping key
Phenotype
MIM number
Gene/Locus Gene/Locus
MIM number
1p34.2 Developmental and epileptic encephalopathy 18 AR 3 615476 SZT2 615463
1p34.1 Developmental and epileptic encephalopathy 15 AR 3 615006 ST3GAL3 606494
1p32.3 Developmental and epileptic encephalopathy 75 AR 3 618437 PARS2 612036
1p31.3 Developmental and epileptic encephalopathy 23 AR 3 615859 DOCK7 615730
1p13.3 Developmental and epileptic encephalopathy 32 AD 3 616366 KCNA2 176262
1q23.2 Developmental and epileptic encephalopathy 98 AD 3 619605 ATP1A2 182340
1q25.3 Developmental and epileptic encephalopathy 69 AD 3 618285 CACNA1E 601013
1q31.3 Developmental and epileptic encephalopathy 57 AD 3 617771 KCNT2 610044
1q42.11 Developmental and epileptic encephalopathy 100 AD 3 619777 FBXO28 609100
1q42.2 Developmental and epileptic encephalopathy 38 AR 3 617020 ARV1 611647
1q44 Developmental and epileptic encephalopathy 54 AD 3 617391 HNRNPU 602869
2p23.3 Developmental and epileptic encephalopathy 50 AR 3 616457 CAD 114010
2p15 ?Developmental and epileptic encephalopathy 88 AR 3 618959 MDH1 154200
2p15 Developmental and epileptic encephalopathy 83 AR 3 618744 UGP2 191760
2q24.3 Developmental and epileptic encephalopathy 62 AD 3 617938 SCN3A 182391
2q24.3 Developmental and epileptic encephalopathy 11 AD 3 613721 SCN2A 182390
2q24.3 Developmental and epileptic encephalopathy 6B, non-Dravet AD 3 619317 SCN1A 182389
2q24.3 Dravet syndrome AD 3 607208 SCN1A 182389
2q31.1 Developmental and epileptic encephalopathy 89 AR 3 619124 GAD1 605363
2q31.1 Developmental and epileptic encephalopathy 39 AR 3 612949 SLC25A12 603667
2q32.2 Developmental and epileptic encephalopathy 71 AR 3 618328 GLS 138280
3p22.1 Developmental and epileptic encephalopathy 68 AR 3 618201 TRAK1 608112
3p21.31 ?Developmental and epileptic encephalopathy 86 AR 3 618910 DALRD3 618904
3p21.31 Developmental and epileptic encephalopathy 102 AR 3 619881 SLC38A3 604437
3q13.31 Developmental and epileptic encephalopathy 93 AD 3 618012 ATP6V1A 607027
3q22.1 Developmental and epileptic encephalopathy 44 AR 3 617132 UBA5 610552
3q25.1 Developmental and epileptic encephalopathy 73 AD 3 618379 RNF13 609247
3q28-q29 Developmental and epileptic encephalopathy 47 AD 3 617166 FGF12 601513
4p16.3 Developmental and epileptic encephalopathy 63 AR 3 617976 CPLX1 605032
4p14 Developmental and epileptic encephalopathy 84 AR 3 618792 UGDH 603370
4p12 ?Developmental and epileptic encephalopathy 40 AR 3 617065 GUF1 617064
4p12 Developmental and epileptic encephalopathy 78 AD 3 618557 GABRA2 137140
4p12 Developmental and epileptic encephalopathy 45 AD 3 617153 GABRB1 137190
4q24 Developmental and epileptic encephalopathy 91 AD 3 617711 PPP3CA 114105
4q35.1 Developmental and epileptic encephalopathy 106 AR 3 620028 UFSP2 611482
5p12 Developmental and epileptic encephalopathy 24 AD 3 615871 HCN1 602780
5q33.3 Developmental and epileptic encephalopathy 65 AD 3 618008 CYFIP2 606323
5q34 Developmental and epileptic encephalopathy 92 AD 3 617829 GABRB2 600232
5q34 Developmental and epileptic encephalopathy 19 AD 3 615744 GABRA1 137160
5q34 Developmental and epileptic encephalopathy 74 AD 3 618396 GABRG2 137164
6p24.1 Developmental and epileptic encephalopathy 70 AD 3 618298 PHACTR1 608723
6p21.1 Developmental and epileptic encephalopathy 60 AR 3 617929 CNPY3 610774
6q21 Developmental and epileptic encephalopathy 87 AD 3 618916 CDK19 614720
7q11.23 Developmental and epileptic encephalopathy 51 AR 3 617339 MDH2 154100
7q11.23 Developmental and epileptic encephalopathy 56 AD 3 617665 YWHAG 605356
7q21.11 Developmental and epileptic encephalopathy 110 AR 3 620149 CACNA2 114204
7q21.12 Developmental and epileptic encephalopathy 61 AR 3 617933 ADAM22 603709
7q22.1 Developmental and epileptic encephalopathy 76 AR 3 618468 ACTL6B 612458
8p21.3 Developmental and epileptic encephalopathy 64 AD 3 618004 RHOBTB2 607352
9q21.33 Developmental and epileptic encephalopathy 58 AD 3 617830 NTRK2 600456
9q22.33 Developmental and epileptic encephalopathy 59 AD 3 617904 GABBR2 607340
9q31.3 Developmental and epileptic encephalopathy 37 AR 3 616981 FRRS1L 604574
9q34.11 Developmental and epileptic encephalopathy 4 AD, AR 3 612164 STXBP1 602926
9q34.11 Developmental and epileptic encephalopathy 31B, autosomal recessive AR 3 620352 DNM1 602377
9q34.11 Developmental and epileptic encephalopathy 31A, autosomal dominant AD 3 616346 DNM1 602377
9q34.11 Developmental and epileptic encephalopathy 5 AD 3 613477 SPTAN1 182810
9q34.3 Developmental and epileptic encephalopathy 14 AD 3 614959 KCNT1 608167
9q34.3 Developmental and epileptic encephalopathy 101 AR 3 619814 GRIN1 138249
10p14 Developmental and epileptic encephalopathy 97 AD 3 619561 CELF2 602538
11p15.5 Developmental and epileptic encephalopathy 3 AR 3 609304 SLC25A22 609302
11p15.4 Developmental and epileptic encephalopathy 49 AR 3 617281 DENND5A 617278
11p13 Developmental and epileptic encephalopathy 41 AD 3 617105 SLC1A2 600300
12p13.31 Developmental and epileptic encephalopathy 21 AR 3 615833 NECAP1 611623
12p13.1 Developmental and epileptic encephalopathy 27 AD 3 616139 GRIN2B 138252
12q13.13 Developmental and epileptic encephalopathy 13 AD 3 614558 SCN8A 600702
12q21.1 Developmental and epileptic encephalopathy 103 AD 3 619913 KCNC2 176256
12q24.11-q24.12 Developmental and epileptic encephalopathy 67 AD 3 618141 CUX2 610648
14q23.2 Developmental and epileptic encephalopathy 112 AD 3 620537 KCNH5 605716
14q32.33 Developmental and epileptic encephalopathy 66 AD 3 618067 PACS2 610423
15q12 Developmental and epileptic encephalopathy 43 AD 3 617113 GABRB3 137192
15q12 Developmental and epileptic encephalopathy 79 AD 3 618559 GABRA5 137142
15q21.2 Developmental and epileptic encephalopathy 81 AR 3 618663 DMXL2 612186
15q21.3 Developmental and epileptic encephalopathy 80 AR 3 618580 PIGB 604122
15q25.2 Developmental and epileptic encephalopathy 48 AR 3 617276 AP3B2 602166
15q26.1 Developmental and epileptic encephalopathy 94 AD 3 615369 CHD2 602119
16p13.3 Multiple congenital anomalies-hypotonia-seizures syndrome 4 AR 3 618548 PIGQ 605754
16p13.3 Developmental and epileptic encephalopathy 16 AR 3 615338 TBC1D24 613577
16q13 Developmental and epileptic encephalopathy 17 AD 3 615473 GNAO1 139311
16q21 Developmental and epileptic encephalopathy 82 AR 3 618721 GOT2 138150
16q22.1 Developmental and epileptic encephalopathy 29 AR 3 616339 AARS1 601065
16q23.1-q23.2 Developmental and epileptic encephalopathy 28 AR 3 616211 WWOX 605131
17p13.1 Developmental and epileptic encephalopathy 25, with amelogenesis imperfecta AR 3 615905 SLC13A5 608305
17q11.2 Developmental and epileptic encephalopathy 95 AR 3 618143 PIGS 610271
17q12 Developmental and epileptic encephalopathy 72 AD 3 618374 NEUROD2 601725
17q21.2 Developmental and epileptic encephalopathy 104 AD 3 619970 ATP6V0A1 192130
17q21.31 Developmental and epileptic encephalopathy 96 AD 3 619340 NSF 601633
17q25.1 Developmental and epileptic encephalopathy 105 with hypopituitarism AR 3 619983 HID1 605752
19p13.3 Developmental and epileptic encephalopathy 109 AD 3 620145 FZR1 603619
19p13.13 Developmental and epileptic encephalopathy 42 AD 3 617106 CACNA1A 601011
19p13.11 Developmental and epileptic encephalopathy 108 AD 3 620115 MAST3 612258
19q13.11 Developmental and epileptic encephalopathy 52 AR 3 617350 SCN1B 600235
19q13.2 Developmental and epileptic encephalopathy 99 AD 3 619606 ATP1A3 182350
19q13.33 Developmental and epileptic encephalopathy 46 AD 3 617162 GRIN2D 602717
19q13.33 Microcephaly, seizures, and developmental delay AR 3 613402 PNKP 605610
20p13 Developmental and epileptic encephalopathy 35 AR 3 616647 ITPA 147520
20p12.3 Developmental and epileptic encephalopathy 12 AR 3 613722 PLCB1 607120
20p11.21 Developmental and epileptic encephalopathy 107 AR 3 620033 NAPB 611270
20q13.12 Developmental and epileptic encephalopathy 34 AR 3 616645 SLC12A5 606726
20q13.13 Developmental and epileptic encephalopathy 26 AD 3 616056 KCNB1 600397
20q13.33 Developmental and epileptic encephalopathy 7 AD 3 613720 KCNQ2 602235
20q13.33 Developmental and epileptic encephalopathy 33 AD 3 616409 EEF1A2 602959
21q22.11 Developmental and epileptic encephalopathy 53 AR 3 617389 SYNJ1 604297
21q22.13 Developmental and epileptic encephalopathy 55 AR 3 617599 PIGP 605938
21q22.3 Developmental and epileptic encephalopathy 30 AD 3 616341 SIK1 605705
22q12.2-q12.3 Developmental and epileptic encephalopathy 111 AR 3 620504 DEPDC5 614191
Xp22.2 Multiple congenital anomalies-hypotonia-seizures syndrome 2 XLR 3 300868 PIGA 311770
Xp22.13 Developmental and epileptic encephalopathy 2 XLD 3 300672 CDKL5 300203
Xp21.3 Developmental and epileptic encephalopathy 1 XLR 3 308350 ARX 300382
Xp11.23 Congenital disorder of glycosylation, type IIm SMo, XLD 3 300896 SLC35A2 314375
Xp11.22 Developmental and epileptic encephalopathy 85, with or without midline brain defects XLD 3 301044 SMC1A 300040
Xq11.1 Developmental and epileptic encephalopathy 8 XL 3 300607 ARHGEF9 300429
Xq22.1 Developmental and epileptic encephalopathy 9 XL 3 300088 PCDH19 300460
Xq23 Developmental and epileptic encephalopathy 36 XL 3 300884 ALG13 300776
Xq26.3-q27.1 Developmental and epileptic encephalopathy 90 XLD, XLR 3 301058 FGF13 300070

TEXT

A number sign (#) is used with this entry because of evidence that developmental and epileptic encephalopathy-6B (DEE6B) is caused by heterozygous mutation in the SCN1A gene (182389) on chromosome 2q24.

Heterozygous mutation in the SCN1A gene also causes Dravet syndrome (DEE6A; 607208), which has overlapping but less severe features.


Description

Developmental and epileptic encephalopathy-6B (DEE6B) is a severe neurodevelopmental disorder characterized by early-infantile seizure onset, profoundly impaired intellectual development, and a hyperkinetic movement disorder. Brain imaging usually shows progressive atrophy and other abnormalities (summary by Sadleir et al., 2017).


Clinical Features

Ohashi et al. (2014) reported a 6-year-old Japanese girl, born of unrelated parents, who presented with multifocal seizures at 2 to 3 months of age. The seizures evolved to frequent episodes of hyperthermia-induced status epilepticus. Around 6 months of age, she developed a hyperkinetic movement disorder with sudden jerky movements resembling chorea and ballismus, as well as hand stereotypies. She had profound developmental delay with poor overall growth, inability to speak, sit, or walk, spastic quadriplegia, and no purposeful hand movements. Brain imaging showed progressive cortical and white matter atrophy, thin corpus callosum, and impaired myelination. She had mild nonspecific dysmorphic features. The authors noted that the phenotype was severe and atypical for Dravet syndrome.

Sadleir et al. (2017) reported 9 unrelated children, ranging from 3 to 12 years of age, with a severe epileptic encephalopathy. Two of the patients (patients 3 and 4) were previously reported by Dhamija et al. (2014). The 9 patients presented with various types of seizures at a mean age of 9 weeks (range 6 to 12 weeks) after normal early development. Seizure types included infantile spasms, tonic-clonic, hemiclonic, myoclonic, and tonic; 8 patients had episodes of status epilepticus. Several had seizures associated with fever or illness; most seizures were intractable to multiple medications. EEG showed multifocal discharges, generalized spike and slow waves, and diffuse background slowing. Brain imaging showed multiple variable abnormalities, including generalized cerebral atrophy, dysmorphic corpus callosum, small hippocampus, and progressive white matter abnormalities. All had profoundly impaired development, with inability to walk independently, absent speech, and poor eye contact; most were tube-fed. Periods of neurologic regression were also observed. Other prominent features included axial hypotonia, limb hypertonia, dystonia, choreoathetosis, orofacial myoclonus or hyperkinesia, nystagmus, ataxia, and generalized or multifocal myoclonic movements. A few patients had nonspecific dysmorphic features, such as microcephaly, hypertelorism, and scoliosis. One patient died at age 10 years. In their paper, Dhamija et al. (2014) found subtle sleep disturbances in their patients with SCN1A mutations.

Harkin et al. (2007) reported a 5-year-old patient (patient 78) with onset of seizures at 2 months of age. The patient had severely impaired intellectual development and increased muscle tone. Another patient (patient 61) with DEE6B was noted to have severe myoclonic epilepsy of infancy (SMEI)-borderland (SMEB, which refers to patients who lack several of the key features of SMEI such as myoclonic seizures or generalized spike-wave activity), but clinical details were limited.


Inheritance

The heterozygous mutations in the SCN1A gene that were identified in patients with DEE6B by Sadleir et al. (2017) occurred de novo.


Molecular Genetics

In a 6-year-old Japanese girl with DEE6B, Ohashi et al. (2014) identified a de novo heterozygous missense mutation in the SCN1A gene (V422L; 182389.0025). The mutation, which was found by whole-exome sequencing, was not present in the Exome Sequencing Project or in 408 in-house Japanese controls. Functional studies of the variant were not performed.

In 8 unrelated patients with DEE6B, Sadleir et al. (2017) identified a de novo recurrent heterozygous missense mutation in the SCN1A gene (T226M; 182389.0026). Another patient (patient 9) carried a de novo heterozygous P1345S mutation (182389.0027). Functional studies of the variants were not performed, but the authors speculated a gain-of-function effect.

In a 5-year-old patient (patient 78) with DEE6B, Harkin et al. (2007) identified a de novo heterozygous T226M mutation in the SCN1A gene. Another patient (patient 61) also carried this mutation. Functional studies of the variant were not performed. The patients were part of a cohort of 188 patients with DEE who were examined for mutations in the SCN1A gene.


REFERENCES

  1. Dhamija, R., Erickson, M. K., St. Louis, E. K., Wirrell, E., Kotagal, S. Sleep abnormalities in children with Dravet syndrome. Pediat. Neurol. 50: 474-478, 2014. [PubMed: 24656210, related citations] [Full Text]

  2. Harkin, L. A., McMahon, J. M., Iona, X., Dibbens, L., Pelekanos, J. T., Zuberi, S. M., Sadleir, L. G., Andermann, E., Gill, D., Farrell, K., Connolly, M., Stanley, T., and 12 others. The spectrum of SCN1A-related infantile epileptic encephalopathies. Brain 130: 843-852, 2007. [PubMed: 17347258, related citations] [Full Text]

  3. Ohashi, T., Akasaka, N., Kobayashi, Y., Magara, S., Kawashima, H., Matsumoto, N., Saitsu, H., Tohyama, J. Infantile epileptic encephalopathy with a hyperkinetic movement disorder and hand stereotypies associated with a novel SCN1A mutation. Epileptic Disord. 16: 208-212, 2014. [PubMed: 24776920, related citations] [Full Text]

  4. Sadleir, L. G., Mountier, E. I., Gill, D., Davis, S., Joshi, C., DeVile, C., Kurian, M. A., Mandelstam, S., Wirrell, E., Nickels, K. C., Murali, H. R., Carvill, G., Myers, C. T., Mefford, H. C., Scheffer, I. E. Not all SCN1A epileptic encephalopathies are Dravet syndrome: early profound thr226met phenotype. Neurology 89: 1035-1042, 2017. [PubMed: 28794249, related citations] [Full Text]


Creation Date:
Cassandra L. Kniffin : 05/06/2021
carol : 05/18/2021
alopez : 05/17/2021
ckniffin : 05/10/2021

# 619317

DEVELOPMENTAL AND EPILEPTIC ENCEPHALOPATHY 6B; DEE6B


ORPHA: 442835;   DO: 0070379;  


Phenotype-Gene Relationships

Location Phenotype Phenotype
MIM number
Inheritance Phenotype
mapping key
Gene/Locus Gene/Locus
MIM number
2q24.3 Developmental and epileptic encephalopathy 6B, non-Dravet 619317 Autosomal dominant 3 SCN1A 182389

TEXT

A number sign (#) is used with this entry because of evidence that developmental and epileptic encephalopathy-6B (DEE6B) is caused by heterozygous mutation in the SCN1A gene (182389) on chromosome 2q24.

Heterozygous mutation in the SCN1A gene also causes Dravet syndrome (DEE6A; 607208), which has overlapping but less severe features.


Description

Developmental and epileptic encephalopathy-6B (DEE6B) is a severe neurodevelopmental disorder characterized by early-infantile seizure onset, profoundly impaired intellectual development, and a hyperkinetic movement disorder. Brain imaging usually shows progressive atrophy and other abnormalities (summary by Sadleir et al., 2017).


Clinical Features

Ohashi et al. (2014) reported a 6-year-old Japanese girl, born of unrelated parents, who presented with multifocal seizures at 2 to 3 months of age. The seizures evolved to frequent episodes of hyperthermia-induced status epilepticus. Around 6 months of age, she developed a hyperkinetic movement disorder with sudden jerky movements resembling chorea and ballismus, as well as hand stereotypies. She had profound developmental delay with poor overall growth, inability to speak, sit, or walk, spastic quadriplegia, and no purposeful hand movements. Brain imaging showed progressive cortical and white matter atrophy, thin corpus callosum, and impaired myelination. She had mild nonspecific dysmorphic features. The authors noted that the phenotype was severe and atypical for Dravet syndrome.

Sadleir et al. (2017) reported 9 unrelated children, ranging from 3 to 12 years of age, with a severe epileptic encephalopathy. Two of the patients (patients 3 and 4) were previously reported by Dhamija et al. (2014). The 9 patients presented with various types of seizures at a mean age of 9 weeks (range 6 to 12 weeks) after normal early development. Seizure types included infantile spasms, tonic-clonic, hemiclonic, myoclonic, and tonic; 8 patients had episodes of status epilepticus. Several had seizures associated with fever or illness; most seizures were intractable to multiple medications. EEG showed multifocal discharges, generalized spike and slow waves, and diffuse background slowing. Brain imaging showed multiple variable abnormalities, including generalized cerebral atrophy, dysmorphic corpus callosum, small hippocampus, and progressive white matter abnormalities. All had profoundly impaired development, with inability to walk independently, absent speech, and poor eye contact; most were tube-fed. Periods of neurologic regression were also observed. Other prominent features included axial hypotonia, limb hypertonia, dystonia, choreoathetosis, orofacial myoclonus or hyperkinesia, nystagmus, ataxia, and generalized or multifocal myoclonic movements. A few patients had nonspecific dysmorphic features, such as microcephaly, hypertelorism, and scoliosis. One patient died at age 10 years. In their paper, Dhamija et al. (2014) found subtle sleep disturbances in their patients with SCN1A mutations.

Harkin et al. (2007) reported a 5-year-old patient (patient 78) with onset of seizures at 2 months of age. The patient had severely impaired intellectual development and increased muscle tone. Another patient (patient 61) with DEE6B was noted to have severe myoclonic epilepsy of infancy (SMEI)-borderland (SMEB, which refers to patients who lack several of the key features of SMEI such as myoclonic seizures or generalized spike-wave activity), but clinical details were limited.


Inheritance

The heterozygous mutations in the SCN1A gene that were identified in patients with DEE6B by Sadleir et al. (2017) occurred de novo.


Molecular Genetics

In a 6-year-old Japanese girl with DEE6B, Ohashi et al. (2014) identified a de novo heterozygous missense mutation in the SCN1A gene (V422L; 182389.0025). The mutation, which was found by whole-exome sequencing, was not present in the Exome Sequencing Project or in 408 in-house Japanese controls. Functional studies of the variant were not performed.

In 8 unrelated patients with DEE6B, Sadleir et al. (2017) identified a de novo recurrent heterozygous missense mutation in the SCN1A gene (T226M; 182389.0026). Another patient (patient 9) carried a de novo heterozygous P1345S mutation (182389.0027). Functional studies of the variants were not performed, but the authors speculated a gain-of-function effect.

In a 5-year-old patient (patient 78) with DEE6B, Harkin et al. (2007) identified a de novo heterozygous T226M mutation in the SCN1A gene. Another patient (patient 61) also carried this mutation. Functional studies of the variant were not performed. The patients were part of a cohort of 188 patients with DEE who were examined for mutations in the SCN1A gene.


REFERENCES

  1. Dhamija, R., Erickson, M. K., St. Louis, E. K., Wirrell, E., Kotagal, S. Sleep abnormalities in children with Dravet syndrome. Pediat. Neurol. 50: 474-478, 2014. [PubMed: 24656210] [Full Text: https://doi.org/10.1016/j.pediatrneurol.2014.01.017]

  2. Harkin, L. A., McMahon, J. M., Iona, X., Dibbens, L., Pelekanos, J. T., Zuberi, S. M., Sadleir, L. G., Andermann, E., Gill, D., Farrell, K., Connolly, M., Stanley, T., and 12 others. The spectrum of SCN1A-related infantile epileptic encephalopathies. Brain 130: 843-852, 2007. [PubMed: 17347258] [Full Text: https://doi.org/10.1093/brain/awm002]

  3. Ohashi, T., Akasaka, N., Kobayashi, Y., Magara, S., Kawashima, H., Matsumoto, N., Saitsu, H., Tohyama, J. Infantile epileptic encephalopathy with a hyperkinetic movement disorder and hand stereotypies associated with a novel SCN1A mutation. Epileptic Disord. 16: 208-212, 2014. [PubMed: 24776920] [Full Text: https://doi.org/10.1684/epd.2014.0649]

  4. Sadleir, L. G., Mountier, E. I., Gill, D., Davis, S., Joshi, C., DeVile, C., Kurian, M. A., Mandelstam, S., Wirrell, E., Nickels, K. C., Murali, H. R., Carvill, G., Myers, C. T., Mefford, H. C., Scheffer, I. E. Not all SCN1A epileptic encephalopathies are Dravet syndrome: early profound thr226met phenotype. Neurology 89: 1035-1042, 2017. [PubMed: 28794249] [Full Text: https://doi.org/10.1212/WNL.0000000000004331]


Creation Date:
Cassandra L. Kniffin : 05/06/2021

Edit History:
carol : 05/18/2021
alopez : 05/17/2021
ckniffin : 05/10/2021