rs398123679
Variant summary
Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3PP5
The NM_002225.5(IVD):c.1066G>A(p.Asp356Asn) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_002225.5 missense, splice_region
Scores
Clinical Significance
Conservation
Publications
- isovaleric acidemiaInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Myriad Women’s Health, G2P, ClinGen
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ACMG classification
Our verdict: Uncertain_significance. The variant received 4 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| IVD | NM_002225.5 | c.1066G>A | p.Asp356Asn | missense_variant, splice_region_variant | Exon 11 of 12 | ENST00000487418.8 | NP_002216.3 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| IVD | ENST00000487418.8 | c.1066G>A | p.Asp356Asn | missense_variant, splice_region_variant | Exon 11 of 12 | 1 | NM_002225.5 | ENSP00000418397.3 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 exome Cov.: 33
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
not provided Uncertain:3
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Reported in a cohort of individuals with inborn errors of metabolism (PMID: 32778825); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); Also known as p.(D327N) and p.(D356N); This variant is associated with the following publications: (PMID: 32778825) -
Isovaleryl-CoA dehydrogenase deficiency Pathogenic:2
This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 359 of the IVD protein (p.Asp359Asn). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of isovaleric acidemia (Invitae). ClinVar contains an entry for this variant (Variation ID: 94050). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
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not specified Uncertain:1
Variant summary: IVD c.1066G>A (p.Asp356Asn) results in a conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251470 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1066G>A has been observed in an inborn error of metabolism (Adhikari_2020). These report(s) do not provide unequivocal conclusions about association of the variant with Isovaleryl-CoA Dehydrogenase Deficiency. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication have been ascertained in the context of this evaluation (PMID: 32778825). ClinVar contains an entry for this variant (Variation ID: 94050). Based on the evidence outlined above, the variant was classified as uncertain significance. -
IVD-related disorder Uncertain:1
The IVD c.1075G>A variant is predicted to result in the amino acid substitution p.Asp359Asn. This variant has been reported in a study of newborn screening for inborn errors of metabolism; however, detailed clinical information was not available (Table S5, Adhikari et al. 2020. PubMed ID: 32778825). This variant has not been reported in a large population database, indicating this variant is rare. This variant has been described in cases of isovaleryl-CoA dehydrogenase deficiency in ClinVar and its classification ranges from uncertain to pathogenic (https://www.ncbi.nlm.nih.gov/clinvar/variation/94050/). An alternate nucleotide change affecting the same amino acid (p.Asp359Gly) has been reported in an individual with isovaleric acidemia (Li et al. 2019. PubMed ID: 31442447). Although we suspect that the c.1075G>A (p.Asp359Asn) variant may be pathogenic, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at