Early onset or syndromic epilepsy
Gene: PPT1
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
AR neuronal ceroid lipofuscinosis 1 (CLN1). Classic infantile onset, seizures have been reported along with other features of this metabolic disease. Vesa et al, 1995 - hom mutation R122W in patients dfrom 40/42 Finnsh CLN1 families - founder effect. Mitchison et al, 1998 - hom or compound het in 11 patients with CLN1. Das et al, 1998, 19 diff mutations in 57 of 58 mutated alleles from 29 patient derived cell lines. R151* 40% of alleles and T75P 13% of alleles. Functional work done on some variants.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
Ceroid lipofuscinosis neuronal, 256730
Publications
Comment when marking as ready: Sufficient casesCreated: 4 Dec 2018, 10:34 p.m.
Comment on list classification: Numerous variants and cases presenting with seizures.Created: 4 Dec 2018, 10:30 p.m.
Associated with Ceroid lipofuscinosis, neuronal, 1 in OMIM and Gene2Phenotype.
PMID: 7637805 (Vesa et al. 1995) - identified a homozygous mutation (R122W) in the PPT1 gene in patients with infantile-onset CLN1 from 40 of 42 Finnish families. The findings were consistent with a founder effect. The parents were carriers. Clinical phenotypes of patients are not given.
PMID: 9425237 (Mitchison et al. 1998) - homozygosity or compound heterozygosity for mutations in the PPT1 gene in 10 families with juvenile-onset CLN1. 5 mutations observed and in all cases followed a Mendelian pattern of inheritance. Epilepsy was observed in patients from 7 families, with onset from the age of 7.
PMID: 9664077 (Das et al. 1998) reports 19 different mutations in the PPT1 gene 29 patient-derived cell lines. 8 patients presented with seizures.Created: 4 Dec 2018, 10:30 p.m.
Seizures are part of the phenotype of this metabolic disorder.Created: 19 Aug 2018, 11:33 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Ceroid lipofuscinosis, neuronal, 1, MIM#256730
Variants in this GENE are reported as part of current diagnostic practice
"PPT" was submitted by an expert, which is most likely to be this HGNC-approved symbol.Created: 1 Jul 2015, 3:16 p.m.
Source Wessex and West Midlands GLH was added to PPT1.
Source NHS GMS was added to PPT1.
Ellen McDonagh: "PPT" was submitted by an expe
Gene: ppt1 has been classified as Green List (High Evidence).
Phenotypes for gene: PPT1 were changed from to Ceroid lipofuscinosis, neuronal, 1 256730
Publications for gene: PPT1 were set to
Mode of inheritance for gene: PPT1 was changed from to BIALLELIC, autosomal or pseudoautosomal
Gene: ppt1 has been classified as Green List (High Evidence).
Expert Review Amber was added to PPT1. Panel: Genetic Epilepsy Syndromes
Victorian Clinical Genetics Services was added to PPT1. Panel: Genetic Epilepsy Syndromes
PPT1 was added to Genetic Epilepsy Syndromes panel. Sources: Expert,Expert Review Red
PPT1 was created by Sarah Leigh