Activity

Filter

Cancel
Date Panel Item Activity
12 actions
Intellectual disability - microarray and sequencing v3.657 GOT2 Arina Puzriakova Tag watchlist was removed from gene: GOT2.
Intellectual disability - microarray and sequencing v3.657 GOT2 Arina Puzriakova Phenotypes for gene: GOT2 were changed from Global developmental delay; Intellectual disability; Seizures; Increased serum lactate; Hyperammonemia; Microcephaly; Failure to thrive; Feeding difficulties; Abnormality of nervous system morphology to Epileptic encephalopathy, early infantile, 82, OMIM:618721; Developmental and epileptic encephalopathy, 82, MONDO:0032880
Intellectual disability - microarray and sequencing v3.656 GOT2 Arina Puzriakova Classified gene: GOT2 as Amber List (moderate evidence)
Intellectual disability - microarray and sequencing v3.656 GOT2 Arina Puzriakova Added comment: Comment on list classification: ID of relevant severity to this panel (severe-to-profound) is reported in 4/4 individuals (PMID:31422819). However, intellectual impairment was secondary to epilepsy and there is no evidence of neurodevelopmental delay preceding the onset of seizures. Therefore, maintaining Amber rating on this panel (GOT2 is already Green on the Genetic epilepsy syndromes (v2.236) panel)
Intellectual disability - microarray and sequencing v3.656 GOT2 Arina Puzriakova Gene: got2 has been classified as Amber List (Moderate Evidence).
Intellectual disability - microarray and sequencing v3.655 GOT2 Arina Puzriakova commented on gene: GOT2
Intellectual disability - microarray and sequencing v3.0 GOT2 Zornitza Stark reviewed gene: GOT2: Rating: GREEN; Mode of pathogenicity: None; Publications: 31422819; Phenotypes: Epileptic encephalopathy, early infantile, 82, MIM# 618721; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal; Current diagnostic: yes
Intellectual disability - microarray and sequencing v2.1018 GOT2 Catherine Snow Tag treatable tag was added to gene: GOT2.
Tag watchlist tag was added to gene: GOT2.
Intellectual disability - microarray and sequencing v2.1018 GOT2 Catherine Snow Classified gene: GOT2 as Amber List (moderate evidence)
Intellectual disability - microarray and sequencing v2.1018 GOT2 Catherine Snow Gene: got2 has been classified as Amber List (Moderate Evidence).
Intellectual disability - microarray and sequencing v2.1017 GOT2 Catherine Snow reviewed gene: GOT2: Rating: AMBER; Mode of pathogenicity: None; Publications: 31422819; Phenotypes: Global developmental delay, Intellectual disability, Seizures; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal
Intellectual disability - microarray and sequencing v2.1015 GOT2 Konstantinos Varvagiannis gene: GOT2 was added
gene: GOT2 was added to Intellectual disability. Sources: Literature
Mode of inheritance for gene: GOT2 was set to BIALLELIC, autosomal or pseudoautosomal
Publications for gene: GOT2 were set to 31422819
Phenotypes for gene: GOT2 were set to Global developmental delay; Intellectual disability; Seizures; Increased serum lactate; Hyperammonemia; Microcephaly; Failure to thrive; Feeding difficulties; Abnormality of nervous system morphology
Penetrance for gene: GOT2 were set to Complete
Review for gene: GOT2 was set to GREEN
Added comment: van Karnebeek et al. (2019 - PMID: 31422819) report on 4 individuals from 3 families, with biallelic GOT2 pathogenic variants (3 missense SNVs and 1 in-frame deletion).

The phenotype corresponded to a metabolic encephalopathy with onset of epilepsy in the first year of life (4/4) with DD and ID (4/4). Additional features included postnatal microcephaly, failure to thrive/feeding difficulties and cerebral anomalies (atrophy and white matter). All subjects had high blood lactate and hyperammonemia. Plasma serine was low in one case (alternative causes were ruled out).

Administration of serine and pyridoxine led to clinical improvement (cessation / better control of seizures) in 2 subjects suggesting that GOT2 deficiency may be amenable to therapeutic intervention. [Treatment could not be started in the 2 further affected individuals].

GOT2 encodes the mitochondrial glutamate oxaloacetate transaminase, a component of the malate-aspartate shuttle (MAS). The latter is important for intracellular NAD(H) redox homeostasis.

The authors provide several lines of evidence that GOT2 deficiency explains the patients' phenotype and metabolic defects incl. :
- Reduced GOT2 protein levels (due to lower expression/impaired stability) and diminished activity in patient fibroblasts (lower activity was also shown for carriers). Rescue of the GOT enzymatic activity was observed upon transduction of patient fibroblasts using lentiviral particles with wt GOT2.
- Impairment of de novo serine biosynthesis in patient (and to a lesser extent in carrier) fibroblasts compared to controls. This was similar in GOT2-knockout HEK293 cells. Serine biosynthesis in these cells was restored by pyruvate supplementation.
- CRISPR/Cas9 Got2-knockout mice resulted in early lethality (during pregnancy). Heterozygous mice were viable and healthy.
- Morpholino knockdown of got2a in zebrafish was shown to perturb embryonic development (smaller head, slow circulation, bend body, brain developmental defects, etc). Pyridoxine and serine in embryo water resulted in milder phenotypes/improved morphant survival. Zebrafish got2a morphants had seizure-like spikes upon EEG that were rescued by treatment with pyridoxine.

GOT2 is not associated with any phenotype in OMIM/G2P.

As a result, this gene can be considered for inclusion in both epilepsy and ID gene panels probably as green (3 families, relevant phenotypes and severity, evidence from cell and animal studies) or amber.

[Please consider inclusion in other relevant panels eg. mitochondrial disorders, metabolic disorders and/or addition of the 'treatable' tag].
Sources: Literature