| Date | Panel | Item | Activity | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Undiagnosed metabolic disorders v1.595 | SLC22A5 | Sarah Leigh changed review comment from: Comment on mode of inheritance: The mode of inheritance for SLC22A5 variants should be BOTH Monoallelic and Biallelic. Although, most of the evidence for symptoms associated SLC22A5 are seen in a patients with biallelic variants (HGNC:10969, OMIM:603377, Gen2Phen, Orphanet:118781, ClinGen), a few individuals heterozygous for SLC22A5 variants have been seen with a milder phenotype (PMID: 10545605; 11261427).; to: Comment on mode of inheritance: The mode of inheritance for SLC22A5 variants should be BIALLELIC, autosomal or pseudoautosomal. Although, heterozygous SLC22A5 variants have been seen in a few cases, these are detectable biochemically and are not associated with clear clinical presentation (PMID: 10545605; 11261427). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.592 | SLC22A5 | Sarah Leigh Added comment: Comment on mode of inheritance: The mode of inheritance for SLC22A5 variants should be BOTH Monoallelic and Biallelic. Although, most of the evidence for symptoms associated SLC22A5 are seen in a patients with biallelic variants (HGNC:10969, OMIM:603377, Gen2Phen, Orphanet:118781, ClinGen), a few individuals heterozygous for SLC22A5 variants have been seen with a milder phenotype (PMID: 10545605; 11261427). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.508 | CPT2 | Arina Puzriakova Added comment: Comment on mode of inheritance: MOI was updated from 'Biallelic' to 'Both mono- and biallelic'. Although most cases are associated with biallelic variants, symptomatic heterozygous patients have also been described (PMID: 15622536; 21913903; 23184072; 24843804). Severity of symptoms tends to correlate with residual CPT enzyme activity but it is plausible that heterozygotes may still be tested under this panel. Both MOIs are listed in OMIM for this phenotype (MIM# 255110) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.497 | CLPB |
Arina Puzriakova Added comment: Comment on mode of inheritance: Updated MOI from 'Biallelic' to 'Both mono- and biallelic'. Association between biallelic variants and disease is well established, with more than 35 affected individuals reported. Recently, six unrelated individuals with de novo monoallelic missense variants in CLPB were identified (PMID: 34140661). The phenotype strongly overlapped with that observed in the recessive disease, including 3-MGA-uria in all cases. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.433 | HS2ST1 |
Ivone Leong gene: HS2ST1 was added gene: HS2ST1 was added to Undiagnosed metabolic disorders. Sources: Literature Mode of inheritance for gene: HS2ST1 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: HS2ST1 were set to 33159882 Phenotypes for gene: HS2ST1 were set to Intellectual disability; dysmorphic features; congenital anomalies Review for gene: HS2ST1 was set to GREEN Added comment: This gene is not associated with a relevant phenotype in OMIM or Gene2Phenotype. Only 2 of 3 unrelated families with affected individuals described in PMID: 33159882 were reported to have ID. The affected individuals in the third family could not be assessed for ID. Other features affected individuals had were muscular hypotonia, hypoplasia/agenesis of corpus callosum, skeletal abnormalities, uni/bilateral renal agenesis (2/3) and craniofacial dysmorphism. There is enough evidence to support a gene-disease association, so this gene has been rated Green. Sources: Literature |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.357 | FDX2 |
Sarah Leigh Added comment: Comment on list classification: Based on reviews from Carl Fratter and Zornitza Stark (below). This gene was added as Green due to the overall review and evidence assessment from the GMS mitochondrial specialist test group, submitted by Carl Fratter (May 2019) on behalf of GMS mitochondrial specialist test group: 3 unrelated familties; iron sulfur pathway. From panel: Possible mitochondrial disorder - nuclear genes (Version 0.187). Promoted from red to amber, based on the expert review by Zornitza Stark (Australian Genomics) and the literature. FDX2 is associated with a phenotype in OMIM and not Gene2Phenotype. PMID: 24281368 describes a patient born of consanguineous Jewish Moroccan patents with episodic mitochondrial myopathy without optic atrophy or reversible leukoencephalopathy. The authors identified a homozygous missense variant in this gene (M1L). PMID: 30010796 describes 6 patients from 2 apparently unrelated Brazilian familes from the same geographical region with episodic mitochondrial myopathy. All affected individuals had the same homozygous variant (P144L). No haplotype analysis was performed. As there are only 2 different variants reported in this gene and no haplotype analysis was performed in PMID: 30010796 it was decided that there is currently not enough evidence to promote this gene to green status. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.348 | COQ7 |
Sarah Leigh gene: COQ7 was added gene: COQ7 was added to Undiagnosed metabolic disorders. Sources: Literature Mode of inheritance for gene: COQ7 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: COQ7 were set to 26084283; 28409910 Phenotypes for gene: COQ7 were set to ?Coenzyme Q10 deficiency, primary, 8 616733 Review for gene: COQ7 was set to GREEN Added comment: This gene was added as Green due to the overall review and evidence assessment from the GMS mitochondrial specialist test group, submitted by Carl Fratter (May 2019) on behalf of GMS mitochondrial specialist test group: 3 unrelated individuals and functional studies. From panel: Possible mitochondrial disorder - nuclear genes (Version 0.187). Sources: Literature |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.312 | SPR | Catherine Snow changed review comment from: Promoted from Amber to Green. This gene is associated with a relevant disease on OMIM and Gene2Phenotype and there is enough evidence to support a gene-disease association. Sepiapterin reductase (SR) deficiency leads to altered tetrahydrobiopterin (BH4) biosynthesis and abnormal biogenic amine metabolism. Most individuals improve with L-dopa administration, therefore treatable tag has been added.; to: Promoted from Amber to Green. This gene is associated with a relevant disease in OMIM and Gene2Phenotype and there is enough evidence to support a gene-disease association. Sepiapterin reductase (SR) deficiency leads to altered tetrahydrobiopterin (BH4) biosynthesis and abnormal biogenic amine metabolism. Most individuals improve with L-dopa administration, therefore treatable tag has been added. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Undiagnosed metabolic disorders v1.82 | RPIA |
Sarah Leigh commented on gene: RPIA: Review by Konstantinos Varvagiannis for the Genetic Epilepsy syndromes panel. 9 Dec 2018, 1:44 a.m. Panel version: 0.1488 Biallelic pathogenic variants in RPIA cause Ribose 5-phosphate isomerase deficiency, MIM 608611. PMID: 14988808 is the first report on the disorder with molecular (incl. genetic) confirmation of the diagnosis. A patient initially investigated for early developmental delay, leukoencephalopathy, seizures with onset at 4 years, with subsequent neurologic regression and peripheral neuropathy at the age of 7, was suspected to have a disorder of the pentose phosphate pathway on the basis of highly elevated polyols on brain MRS and body fluid analysis. Reduced ribose 5-phosphate isomerase activity was shown in fibroblasts. Genetic testing demonstrated the presence of a missense (NM_144563.2:c.404C>T or p.Ala135Val - previously referred to as A61V) as well as a frameshift variant (NM_144563.2:c.762delG or p.Asn255Ilefs). Additional extensive supportive functional studies were published a few years later (PMID: 20499043). [This patient was initially described in PMID: 10589548]. PMID: 28801340 is a report on a second patient. This individual presented with delayed early development (independent walking and speech achieved at 2 and 5 years respectively), seizures and regression at the age of 7 with MRI white matter abnormalities. Review of magnetic resonance spectroscopy (MRS) was suggestive of elevated polyols (arabitol and ribitol). In line with this, genetic testing revealed a homozygous missense variant in RPIA (NM_144563.2:c.592T>C or p.Phe198Leu). Urine analysis confirmed elevated excretion of polyols, thus confirming the diagnosis. PMID: 30088433 reports on a boy with neonatal onset leukoencephalopathy and developmental delay having undergone early metabolic testing and aCGH (the latter at the age of 16 months). Persistance of his delay motivated exome sequencing at the age of approx. 4.5 years which demonstrated 2 RPIA variants (NM_144563.2:c.253G>A or p.Ala85Thr and NM_144563.2:c.347-1G>A). Measurement of ribitol and arabitol in urine demonstrated significant elevations (>20x) consistent with this diagnosis. 2 of the 3 patients described in the literature presented seizures. As a result this gene can be considered for inclusion in this panel as amber. [This gene is also present in the Undiagnosed metabolic disorders gene panel as red. Please consider upgrade based on these further publications.]. Sources: Literature |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||