Early onset or syndromic epilepsy
Gene: SCN8A
Agree that evidence suggests that rare cases of biallelic inheritance of SCN8A variants have been reported with an epilepsy phenotype.Created: 7 Jan 2022, 4:13 p.m. | Last Modified: 7 Jan 2022, 4:13 p.m.
Panel Version: 2.483
Mode of inheritance
BOTH monoallelic and biallelic (but BIALLELIC mutations cause a more SEVERE disease form), autosomal or pseudoautosomal
Publications
Added 'for-review' tag as the MOI has changed since previous sign-off of this panel (version 2.2) and requires review by the Specialist Test Group.Created: 21 Oct 2020, 4:42 p.m. | Last Modified: 21 Oct 2020, 4:42 p.m.
Panel Version: 2.201
The to_be_confirmed_NHSE tag has been added, as further NHSE review is required.Created: 15 Mar 2022, 3:41 p.m. | Last Modified: 15 Mar 2022, 3:41 p.m.
Panel Version: 2.498
Comment on mode of inheritance: The mode of inheritance has been reverted to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown from BOTH monoallelic and biallelic, autosomal or pseudoautosomal, while the strength of the evidence is reviewed.Created: 11 Jan 2022, 11:09 a.m. | Last Modified: 11 Jan 2022, 11:14 a.m.
Panel Version: 2.485
Comment on mode of pathogenicity: Based on report in PMID 31625145, reporting biallelic loss of function SCN8A variants in three cases in two families with severe developmental and epileptic encephalopathy. This differs from the previosly reported gain of function, monoallelic variants (PMID 24194747;22365152).Created: 26 Mar 2020, 3:49 p.m. | Last Modified: 26 Mar 2020, 3:49 p.m.
Panel Version: 2.25
Comment on mode of inheritance: Based on report in PMID 31625145, reporting biallelic loss of function SCN8A variants in three cases in two families with severe developmental and epileptic encephalopathy.Created: 26 Mar 2020, 9:44 a.m. | Last Modified: 26 Mar 2020, 9:44 a.m.
Panel Version: 2.23
Note recent publication of bi-allelic variants causing epilepsy in three individuals from two families. Mono-allelic variants are typically GoF, whereas these variants were shown to be LoF. Parents are said to have had mild learning difficulties. Consider changing mode of inheritance and pathogenicity and associated pipeline settings.Created: 21 Jan 2020, 10:34 a.m. | Last Modified: 21 Jan 2020, 10:34 a.m.
Panel Version: 2.0
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Epileptic encephalopathy, early infantile, 13, MIM# 614558; dominant and recessive
Publications
Mode of pathogenicity
Other
Variants in this GENE are reported as part of current diagnostic practice
Review and rating collated by Tracy Lester (Oxford Medical Genetics Laboratories Oxford University Hospitals NHS Foundation Trust, 2019_02_06) on behalf of Wessex and West Midlands GLH for GMS Neurology specialist test group, for Clinical Indication R59 'Early onset or syndromic epilepsy'. Review contributors: John Taylor and Helen Lord. Suggested gene rating: Green.Created: 6 Aug 2019, 8:38 p.m. | Last Modified: 6 Aug 2019, 8:38 p.m.
Panel Version: 1.189
AD cognitive impairment with/without cerebellar ataxia, AD EIEE 13, AD benign familial infantile seizures. Lots of mutations reported - mostly missense on HGMD pro in assocation with an epilepsy phentoye. Several cases on OMIM with variants detected, arisen de novo. Functional studies have been undertaken for some variants: Veeramah et al, 2012 & de Kovel et al, 2014.Created: 6 Aug 2019, 8:31 p.m. | Last Modified: 6 Aug 2019, 8:31 p.m.
Panel Version: 1.188
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
?Cognitive impairment with or without cerebellar ataxia,614306; Epileptic encephalopathy, early infantile,614558; Seizures, benign familial infantile,617080
Publications
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Cognitive impairment with or without cerebellar ataxia; Intellectual disability; Epileptic encephalopathy, early infantile, 13
Publications
Variants in this GENE are reported as part of current diagnostic practice
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Cognitive impairment with or without cerebellar ataxia; Intellectual disability; Epileptic encephalopathy, early infantile, 13
Publications
Variants in this GENE are reported as part of current diagnostic practice
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Cognitive impairment with or without cerebellar ataxia; Intellectual disability; Epileptic encephalopathy, early infantile, 13
Publications
Variants in this GENE are reported as part of current diagnostic practice
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Cognitive impairment with or without cerebellar ataxia; Intellectual disability; Epileptic encephalopathy, early infantile, 13
Publications
Mode of pathogenicity
loss-of-function (truncating variants and curated list of variants)
Variants in this GENE are reported as part of current diagnostic practice
Comment when marking as ready: Confirmed DD gene and all 4 reviewers agree this should be green. Mode of inheritance confirmed. Mutation consequence summary from G2P is dominant negative.Created: 21 Jan 2016, 12:53 p.m.
Comment on mode of inheritance: Confirmed and not on imprinted gene list.Created: 21 Jan 2016, 11:57 a.m.
Tag to_be_confirmed_NHSE tag was added to gene: SCN8A.
Mode of inheritance for gene: SCN8A was changed from BOTH monoallelic and biallelic, autosomal or pseudoautosomal to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes for gene: SCN8A were changed from ?Cognitive impairment with or without cerebellar ataxia,614306; Epileptic encephalopathy, early infantile,614558; Seizures, benign familial infantile,617080 to Developmental and epileptic encephalopathy 13, OMIM:614558; Seizures, benign familial infantile, 5, OMIM:617080; ?Myoclonus, familial, 2, OMIM:618364
Tag for-review tag was added to gene: SCN8A.
Mode of pathogenicity for gene: SCN8A was changed from Other to Other
Mode of pathogenicity for gene: SCN8A was changed from None to Other
Mode of inheritance for gene: SCN8A was changed from MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted to BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes for gene: SCN8A were changed from Cognitive impairment with or without cerebellar ataxia; Intellectual disability; Epileptic encephalopathy, early infantile, 13 to ?Cognitive impairment with or without cerebellar ataxia,614306; Epileptic encephalopathy, early infantile,614558; Seizures, benign familial infantile,617080
Publications for gene: SCN8A were set to Trudeau et al (2004) J Med Genet 43: 527_530; O'Brien and Meisler (2013) Frontiers in Genet 4(213): 1-9; Veeramah et al (2012) Am J Hum Genet 90: 502_510
Source Wessex and West Midlands GLH was added to SCN8A.
Source NHS GMS was added to SCN8A.
Ellen McDonagh: Comment on mode of inheritance
NIHRBR-RD Consortium SPEED_v3.0_20170404 was added to SCN8A. Panel: Genetic Epilepsy Syndromes
Victorian Clinical Genetics Services was added to SCN8A. Panel: Genetic Epilepsy Syndromes
SCN8A was added to Genetic Epilepsy Syndromes panel. Sources: Expert Review Green,UKGTN,Radboud University Medical Center, Nijmegen,Illumina TruGenome Clinical Sequencing Services
SCN8A was created by Sarah Leigh