rs764618040

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2PP5BP4

The NM_006623.4(PHGDH):​c.374C>T​(p.Thr125Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000248 in 1,613,970 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T125T) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

PHGDH
NM_006623.4 missense

Scores

4
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:2

Conservation

PhyloP100: 1.96

Publications

2 publications found
Variant links:
Genes affected
PHGDH (HGNC:8923): (phosphoglycerate dehydrogenase) This gene encodes the enzyme which is involved in the early steps of L-serine synthesis in animal cells. L-serine is required for D-serine and other amino acid synthesis. The enzyme requires NAD/NADH as a cofactor and forms homotetramers for activity. Mutations in this gene have been found in a family with congenital microcephaly, psychomotor retardation and other symptoms. Multiple alternatively spliced transcript variants have been found, however the full-length nature of most are not known. [provided by RefSeq, Aug 2011]
PHGDH Gene-Disease associations (from GenCC):
  • neurometabolic disorder due to serine deficiency
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • PHGDH deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet
  • Neu-Laxova syndrome 1
    Inheritance: AR Classification: MODERATE Submitted by: G2P
  • Neu-Laxova syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 1-119726868-C-T is Pathogenic according to our data. Variant chr1-119726868-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 373899.
BP4
Computational evidence support a benign effect (MetaRNN=0.2855714). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PHGDHNM_006623.4 linkc.374C>T p.Thr125Met missense_variant Exon 4 of 12 ENST00000641023.2 NP_006614.2 O43175

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PHGDHENST00000641023.2 linkc.374C>T p.Thr125Met missense_variant Exon 4 of 12 NM_006623.4 ENSP00000493175.1 O43175

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152234
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251482
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000253
AC:
37
AN:
1461736
Hom.:
0
Cov.:
30
AF XY:
0.0000248
AC XY:
18
AN XY:
727192
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5732
European-Non Finnish (NFE)
AF:
0.0000288
AC:
32
AN:
1111912
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.459
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152234
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74374
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68052
Other (OTH)
AF:
0.000478
AC:
1
AN:
2094
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.0136242), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.392
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

PHGDH deficiency Pathogenic:1Uncertain:1
Oct 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 125 of the PHGDH protein (p.Thr125Met). This variant is present in population databases (rs764618040, gnomAD 0.003%). This missense change has been observed in individual(s) with clinical features of PHGDH-related conditions (PMID: 29286531). ClinVar contains an entry for this variant (Variation ID: 373899). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt PHGDH protein function. 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. -

Jan 01, 2016
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was classified as: Likely pathogenic. -

Seizure;C0543888:Epileptic encephalopathy Pathogenic:1
Jun 11, 2014
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Oct 13, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.374C>T (p.T125M) alteration is located in exon 4 (coding exon 4) of the PHGDH gene. This alteration results from a C to T substitution at nucleotide position 374, causing the threonine (T) at amino acid position 125 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.37
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.54
D;.;D;.;.;.;.;.
Eigen
Benign
0.045
Eigen_PC
Benign
0.00072
FATHMM_MKL
Benign
0.32
N
LIST_S2
Uncertain
0.92
.;D;T;D;D;D;T;D
M_CAP
Benign
0.030
D
MetaRNN
Benign
0.29
T;T;T;T;T;T;T;T
MetaSVM
Benign
-0.50
T
MutationAssessor
Benign
0.20
N;.;N;.;.;.;.;.
PhyloP100
2.0
PrimateAI
Benign
0.34
T
PROVEAN
Benign
-1.5
.;.;.;.;.;.;N;.
REVEL
Uncertain
0.29
Sift
Benign
0.12
.;.;.;.;.;.;T;.
Sift4G
Benign
0.22
.;.;.;.;.;.;T;.
Polyphen
0.95
P;.;P;.;.;.;.;.
Vest4
0.31
MutPred
0.56
Gain of MoRF binding (P = 0.079);.;Gain of MoRF binding (P = 0.079);Gain of MoRF binding (P = 0.079);Gain of MoRF binding (P = 0.079);Gain of MoRF binding (P = 0.079);Gain of MoRF binding (P = 0.079);.;
MVP
0.87
MPC
0.51
ClinPred
0.69
D
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Varity_R
0.24
gMVP
0.63
Mutation Taster
=26/74
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs764618040; hg19: chr1-120269491; COSMIC: COSV65573170; COSMIC: COSV65573170; API