NM_014297.5:c.487C>T
Variant summary
Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM3_StrongPP1_StrongPM5PS3_SupportingPP4_ModeratePP3
This summary comes from the ClinGen Evidence Repository: The ETHE1 c.487C>T mutation is a missense mutation at the 163 amino acid position where one other pathogenic mutation has been reported (c.488G>A) indicating that this residue is critical to the function of the protein (PM5_moderate). There are multiple lines of computational evidence supporting a deleterious effect (PP3_supporting). Functional studies performed in ETHE1 isolated from E-coli cells demonstrated 10 fold reduced ETHE1 catalytic activity when compared to controls (PS3_supporting; PMID:25198162). The c.487C>T mutation has been reported in four unrelated affected individuals including three who were homozygous for the mutation (PMID:16183799; PMID:16828325; PMID:28698729) and one proband where the c. 487C>T was found in trans with another reportedly pathogenic ETHE1 mutation (PMID:18593870) (PM3_strong). One of these patients demonstrated a clinical phenotype specific to ethylmalonic encephalopathy including chronic diarrhea, petechiae, acrocyanosis, and developmental delay in addition to the biochemical findings urinary ethylmalonic acid and elevated blood C4-acylcarnitine esters and blood C5-acylcarnitines (PP4_moderate; PMID:16828325). A larger family including 7 children has been reported where homozygous c.487C>T mutation was identified in the three affected siblings and segregated with disease in the unaffected siblings (PP1_strong; PMID:14732903). In summary, this variant meets criteria to be classified as pathogenic for ethylmalonic encephalopathy in an autosomal recessive manner. ETHE1-specific ACMG/AMP criteria applied PM5_moderate; PP3_supporting; PS3_supporting; PM3_strong; PP4_moderate; PP1_strong. LINK:https://erepo.genome.network/evrepo/ui/classification/CA115479/MONDO:0011229/014
Frequency
Consequence
NM_014297.5 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Pathogenic. Variant got 14 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
ETHE1 | NM_014297.5 | c.487C>T | p.Arg163Trp | missense_variant | Exon 4 of 7 | ENST00000292147.7 | NP_055112.2 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152146Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.0000239 AC: 6AN: 251460Hom.: 0 AF XY: 0.0000147 AC XY: 2AN XY: 135910
GnomAD4 exome AF: 0.0000137 AC: 20AN: 1461866Hom.: 0 Cov.: 31 AF XY: 0.0000165 AC XY: 12AN XY: 727238
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152146Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1AN XY: 74328
ClinVar
Submissions by phenotype
Ethylmalonic encephalopathy Pathogenic:9Other:1
- -
- -
- -
- -
Variant summary: The ETHE1 c.487C>T (p.Arg163Trp) variant involves the alteration of a conserved nucleotide located at the Metallo-beta-lactamase domain (INterPro). 4/4 in silico tools predict a damaging outcome for this variant (SNPsandGO not captured due to low reliability index). This variant was found in 6/278272 control chromosomes at a frequency of 0.0000216, which does not exceed the estimated maximal expected allele frequency of a pathogenic ETHE1 variant (0.0013229). It has been reported in multiple affected individuals in the homozygous state (Tiranti_2004 and Rocco_2006), and a functional study showed the variant with <10% specific activity compared to wild-type (Henriques_2014). Variants affecting the same codon such as R163Q have also been reported affected individuals, supporting the funcitonal importance of this codon. Taken together, this variant is classified as pathogenic. -
- -
This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 163 of the ETHE1 protein (p.Arg163Trp). This variant is present in population databases (rs28940289, gnomAD 0.008%). This missense change has been observed in individuals with clinical features of ethylmalonic encephalopathy (PMID: 16828325, 18593870, 30864297). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 2317). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt ETHE1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects ETHE1 function (PMID: 25198162). This variant disrupts the p.Arg163 amino acid residue in ETHE1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 2777167, 14732903, 30298498). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
- -
- -
The ETHE1 c.487C>T variant is a missense variant at the 163 amino acid position where one other pathogenic mutation has been reported (c.488G>A) indicating that this residue is critical to the function of the protein (PM5_moderate). There are multiple lines of computational evidence supporting a deleterious effect (PP3_supporting). Functional studies performed in ETHE1 isolated from E-coli cells demonstrated 10 fold reduced ETHE1 catalytic activity when compared to controls (PS3_supporting; PMID:25198162). The c.487C>T mutation has been reported in four unrelated affected individuals including three who were homozygous for the variant (PMID:16183799; PMID:16828325; PMID:28698729) and one proband where c.487C>T was found in trans with another reportedly pathogenic ETHE1 variant (PMID:18593870) (PM3_strong). One of these patients demonstrated a clinical phenotype specific to ethylmalonic encephalopathy including chronic diarrhea, petechiae, acrocyanosis, and developmental delay in addition to the biochemical findings urinary ethylmalonic acid and elevated blood C4-acylcarnitine esters and blood C5-acylcarnitines (PP4_moderate; PMID: 16828325). A larger family including 7 children has been reported where homozygous c.487C>T variant was identified in the three affected siblings and segregated with disease in the unaffected siblings (PP1_strong; PMID:14732903). In summary, this variant meets criteria to be classified as pathogenic for ethylmalonic encephalopathy in an autosomal recessive manner. ETHE1-specific ACMG/AMP criteria applied PM5_moderate; PP3_supporting; PS3_supporting; PM3_strong; PP4_moderate; PP1_strong. -
not provided Pathogenic:1
ETHE1: PM3:Strong, PM2, PM5, PP1:Moderate, PP3, PS3:Supporting -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at