Early onset or syndromic epilepsy
Gene: SLC35A1
Insufficient evidence. Limited number of variants reported and the phenotype association appears to be for congenital disorders of glycosylation, where seizures can be a feature (PMID 23873973, 28856833)Created: 6 Aug 2019, 8:31 p.m. | Last Modified: 6 Aug 2019, 8:31 p.m.
Panel Version: 1.188
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Congenital disorder of glycosylation type IIf, 603585
Publications
As discussed with members of the GMS Neurology Specialist Test Group on the Webex call 22nd November 2019 for Clinical Indication R59 Early onset or syndromic epilepsy: Agreed that there is insufficient evidence to rate this gene Green. Better tested through the metabolic panel. Demoted from Green to Amber.Created: 25 Nov 2019, 9:08 p.m. | Last Modified: 25 Nov 2019, 9:08 p.m.
Panel Version: 1.458
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: Alison Callaway and John Taylor. Suggested gene rating: Amber.Created: 6 Aug 2019, 8:38 p.m. | Last Modified: 6 Aug 2019, 8:38 p.m.
Panel Version: 1.189
Removed watchlist tag after promotion of SLC35A1 to Green.Created: 18 Feb 2019, 3:05 p.m.
Comment on list classification: Updated rating from Amber to Green following clinical agreement from Helen Brittain: Although there are some issues that further cases would help to address, e.g. the inconsistent phenotypic spectrum and the timing of delay in relation to seizures, a recent PMID:30115659 paper (Kauskot et al. 2018) provides a third SLC35A1 case with a seizure phenotype (the first two cases coming from PMID:23873973 and PMID:28856833) and therefore on balance there are sufficient cases to support causation.Created: 18 Feb 2019, 3:04 p.m.
Re-reviewed following promotion of SLC35A1 to Green on the ID panel. In summary, there are 2 existing cases of seizures and SLC35A1 variants (a Turkish patient in PMID:23873973, and a German patient in PMID:28856833). There is a further paper linking SLC35A1 to a glycosylation disorder (PMID:15576474) but without an ID or epilepsy phenotype. A 2018 paper (PMID:30115659) now reports 2 siblings with a haematological phenotype. The authors say that the siblings' phenotypes included delayed psychomotor development, epilepsy, ataxia, microcephaly, choreiform movements, and macrothrombocytopenia, though no futher information is provided.Created: 18 Feb 2019, 3 p.m.
Seizures are part of the phenotype of this metabolic disorder.Created: 21 Aug 2018, 9:40 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Congenital disorder of glycosylation, type IIf, MIM#603585
Publications
Variants in this GENE are reported as part of current diagnostic practice
Gene originally listed on the Intellectual disability panel V2.42.
Comment on list classification: Associated with relevant phenotype in OMIM and as probable Gen2Phen gene. At least 5 variants reported in 3 unrelated cases, however, epileptic seizures were only reported in two cases.Created: 21 Jun 2018, 10:56 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Congenital disorder of glycosylation, type IIf 603585
Publications
Publications for gene: SLC35A1 were set to 23873973; 15576474; 28856833; 30115659
Gene: slc35a1 has been classified as Amber List (Moderate Evidence).
Source Wessex and West Midlands GLH was added to SLC35A1.
Source NHS GMS was added to SLC35A1.
Tag watchlist was removed from gene: SLC35A1.
Gene: slc35a1 has been classified as Green List (High Evidence).
Phenotypes for gene: SLC35A1 were changed from Congenital disorder of glycosylation, type IIf 603585 to Congenital disorder of glycosylation, type IIf, 603585; seizures
Publications for gene: SLC35A1 were set to 23873973; 15576474; 28856833
Sarah Leigh: Gene originally listed on the
Gene: slc35a1 has been classified as Amber List (Moderate Evidence).
Tag watchlist tag was added to gene: SLC35A1.
Gene: slc35a1 has been classified as Amber List (Moderate Evidence).
SLC35A1 was added to Genetic Epilepsy Syndromes panel. Sources: Literature
SLC35A1 was created by Sarah Leigh