Early onset or syndromic epilepsy
Gene: HCCS
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: Red.Created: 6 Aug 2019, 8:38 p.m. | Last Modified: 6 Aug 2019, 8:38 p.m.
Panel Version: 1.189
This gene appears to be predominantly associated with micophthalmia/ocular abnormalities, athough there is a report of an association with MIDAS which can have infantile seizures as a feature, PMID 17033964.Created: 6 Aug 2019, 8:31 p.m. | Last Modified: 6 Aug 2019, 8:31 p.m.
Panel Version: 1.188
Mode of inheritance
X-LINKED: hemizygous mutation in males, monoallelic mutations in females may cause disease (may be less severe, later onset than males)
Phenotypes
Linear skin defects with multiple congenital anomalies, 309801
Publications
Comment when marking as ready: Despite seizures being listed as a common feature in GeneReviews, there is only 1 reported case of epilepsy with with HCCS gene. Therefore, it will remain as an amber gene. I have added the 'watchlist' tag.Created: 3 Dec 2018, 10:34 a.m.
Comment when marking as ready: 'Linear skin defects with multiple congenital anomalies 1' confirmed in both OMIM and Gene2Phenotype and seizure is listed as a phenotype in both.
Neurological involvement is a feature of this disorder and seizures is listed as one of these in GeneReviews. However, only found one patient with a misssense variant in this gene had seizures (PMID: 17033964). This review (PMID: 30374660) states that seizures are a rare symptom in this disorder but mentions that patients with variants in HCCS has been reported to have seizures, they reference this article (PMID: 24735900). I have checked the article and could not find any mention of seizures or epilepsy.Created: 14 Nov 2018, 1:43 p.m.
XLD. Seizures are part of the phenotype of this multi-system disorder.Created: 15 Aug 2018, 12:37 a.m.
Mode of inheritance
Other
Phenotypes
Linear skin defects with multiple congenital anomalies 1, MIM#309801
Variants in this GENE are reported as part of current diagnostic practice
Source Wessex and West Midlands GLH was added to HCCS.
Source NHS GMS was added to HCCS.
Zornitza Stark: XLD. Seizures are part of the
Gene: hccs has been classified as Amber List (Moderate Evidence).
Tag watchlist tag was added to gene: HCCS.
Gene: hccs has been classified as Amber List (Moderate Evidence).
Publications for gene: HCCS were set to
Mode of inheritance for gene: HCCS was changed from to X-LINKED: hemizygous mutation in males, monoallelic mutations in females may cause disease (may be less severe, later onset than males)
Phenotypes for gene: HCCS were changed from to Linear skin defects with multiple congenital anomalies 1, 309801
Expert Review Amber was added to HCCS. Panel: Genetic Epilepsy Syndromes
HCCS was added to Genetic Epilepsy Syndromes panel. Sources: Victorian Clinical Genetics Services
HCCS was created by Sarah Leigh