rs587731325
Variant summary
Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_006623.4(PHGDH):c.1471C>T(p.Arg491Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000195 in 1,613,754 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R491Q) has been classified as Uncertain significance.
Frequency
Consequence
NM_006623.4 missense
Scores
Clinical Significance
Conservation
Publications
- neurometabolic disorder due to serine deficiencyInheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
- PHGDH deficiencyInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet
- Neu-Laxova syndrome 1Inheritance: AR Classification: MODERATE Submitted by: G2P
- Neu-Laxova syndromeInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Likely_benign. The variant received -2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.000243 AC: 37AN: 152208Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.000104 AC: 26AN: 249902 AF XY: 0.000111 show subpopulations
GnomAD4 exome AF: 0.000190 AC: 277AN: 1461428Hom.: 0 Cov.: 31 AF XY: 0.000190 AC XY: 138AN XY: 727020 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.000243 AC: 37AN: 152326Hom.: 0 Cov.: 33 AF XY: 0.000215 AC XY: 16AN XY: 74490 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
PHGDH deficiency Uncertain:3
This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 491 of the PHGDH protein (p.Arg491Trp). This variant is present in population databases (rs587731325, gnomAD 0.02%). This missense change has been observed in individual(s) with phosphoglycerate dehydrogenase deficiency (PMID: 22393170). ClinVar contains an entry for this variant (Variation ID: 496330). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on PHGDH protein function. Experimental studies have shown that this missense change affects PHGDH function (PMID: 33758422). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
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This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
not provided Pathogenic:1Uncertain:1
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Published functional studies demonstrate p.(R491W) reduces PHGDH enzyme activity (PMID: 33758422); In silico analysis suggests that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 22393170, 26960553, 33758422, 32594192) -
not specified Uncertain:1
Variant summary: PHGDH c.1471C>T (p.Arg491Trp) results in a non-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. The variant allele was found at a frequency of 0.0001 in 249902 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in PHGDH causing Phosphoglycerate Dehydrogenase Deficiency (0.0001 vs 0.0026), allowing no conclusion about variant significance. c.1471C>T has been observed in a compound heterozygous individual affected with Phosphoglycerate Dehydrogenase Deficiency and in an individual affected with Macular telangiectasia type 2 (Meneret_2012, Eade_2021). These data do not allow any conclusion about variant significance. Experimental evidence evaluating an impact on protein function demonstrated the variant to have 52% of relative enzyme activity compared to wild-type (Eade_2021). The following publications have been ascertained in the context of this evaluation (PMID: 33758422, 22393170). ClinVar contains an entry for this variant (Variation ID: 496330). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Neu-Laxova syndrome 1 Uncertain:1
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Inborn genetic diseases Uncertain:1
(Méneret, 2012) Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
PHGDH deficiency;C4551478:Neu-Laxova syndrome 1 Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at