NM_000277.3:c.755G>A

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PP4_ModeratePM2PP3PM3PS3

This summary comes from the ClinGen Evidence Repository: PAH-specific ACMG/AMP criteria applied: PM2: ; PP3: tools predict damaging; PS3: BioPKU 3% enzyme activity; 3.8% residual activity (PMID:24401910); PM3: Detected in trans with p.Pro407fs (PMID:7833954); PP4_Moderate: Detected in 2 patients with classic PKU (Phe>1.5mM). BH4 deficiency excluded (PMID:7833954; PMID:9634518). In summary this variant meets criteria to be classified as pathogenic for phenylketonuria in an autosomal recessive manner based on the ACMG/AMP criteria applied as specified by the PAH Expert Panel: (PM2, PP3, PS3, PM3, PP4_Moderate). LINK:https://erepo.genome.network/evrepo/ui/classification/CA229743/MONDO:0009861/006

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

PAH
NM_000277.3 missense

Scores

15
3
1

Clinical Significance

Pathogenic reviewed by expert panel P:12O:1

Conservation

PhyloP100: 7.91
Variant links:
Genes affected
PAH (HGNC:8582): (phenylalanine hydroxylase) This gene encodes a member of the biopterin-dependent aromatic amino acid hydroxylase protein family. The encoded phenylalanine hydroxylase enzyme hydroxylates phenylalanine to tyrosine and is the rate-limiting step in phenylalanine catabolism. Deficiency of this enzyme activity results in the autosomal recessive disorder phenylketonuria. [provided by RefSeq, Aug 2017]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 11 ACMG points.

PS3
For more information check the summary or visit ClinGen Evidence Repository.
PM2
For more information check the summary or visit ClinGen Evidence Repository.
PM3
For more information check the summary or visit ClinGen Evidence Repository.
PP3
For more information check the summary or visit ClinGen Evidence Repository.
PP4
For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PAHNM_000277.3 linkc.755G>A p.Arg252Gln missense_variant Exon 7 of 13 ENST00000553106.6 NP_000268.1 P00439A0A024RBG4
PAHNM_001354304.2 linkc.755G>A p.Arg252Gln missense_variant Exon 8 of 14 NP_001341233.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PAHENST00000553106.6 linkc.755G>A p.Arg252Gln missense_variant Exon 7 of 13 1 NM_000277.3 ENSP00000448059.1 P00439
PAHENST00000307000.7 linkc.740G>A p.Arg247Gln missense_variant Exon 8 of 14 5 ENSP00000303500.2 J3KND8
PAHENST00000549247.6 linkn.514G>A non_coding_transcript_exon_variant Exon 1 of 6 2
PAHENST00000635477.1 linkc.-86G>A upstream_gene_variant 5 ENSP00000489230.1 A0A0U1RQY4

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152030
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.00
GnomAD3 exomes
AF:
0.00000796
AC:
2
AN:
251262
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135780
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000616
AC:
9
AN:
1461852
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
727228
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000504
Gnomad4 SAS exome
AF:
0.0000348
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152030
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74244
show subpopulations
Gnomad4 AFR
AF:
0.0000242
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000240
Hom.:
0
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:12Other:1
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Phenylketonuria Pathogenic:9
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 09, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: PAH c.755G>A (p.Arg252Gln) results in a conservative amino acid change located in the aromatic amino acid hydroxylase, C-terminal domain (IPR019774) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251262 control chromosomes. c.755G>A has been reported in the literature in multiple individuals affected with Phenylalanine Hydroxylase Deficiency (Phenylketonuria) (example, Benit_1994, Liang_2014, Li_2018). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in categorization as a functionally hemizygous variant with less than 10% of normal activity (Li_2018). Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Aug 10, 2018
ClinGen PAH Variant Curation Expert Panel
Significance: Pathogenic
Review Status: reviewed by expert panel
Collection Method: curation

PAH-specific ACMG/AMP criteria applied: PM2: ; PP3: tools predict damaging; PS3: BioPKU 3% enzyme activity; 3.8% residual activity (PMID:24401910); PM3: Detected in trans with p.Pro407fs (PMID:7833954); PP4_Moderate: Detected in 2 patients with classic PKU (Phe>1.5mM). BH4 deficiency excluded (PMID:7833954; PMID:9634518). In summary this variant meets criteria to be classified as pathogenic for phenylketonuria in an autosomal recessive manner based on the ACMG/AMP criteria applied as specified by the PAH Expert Panel: (PM2, PP3, PS3, PM3, PP4_Moderate). -

Sep 01, 2022
3billion
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.001%). It is located in a mutational hot spot and/or well-established functional domain in which established pathogenic variants have been reported. Missense changes are a common disease-causing mechanism. Functional studies provide strong evidence of the variant having a damaging effect on the gene or gene product (PMID: 24401910). In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.94; 3Cnet: 0.99). The variant has been reported to be in trans with a pathogenic variant as either compound heterozygous or homozygous in at least one similarly affected unrelated individual (PMID: 7833954). Different missense changes at the same codon (p.Arg252Gly, p.Arg252Pro, p.Arg252Trp) have been reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000000584 , VCV000102823 , VCV000932252). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -

-
Juno Genomics, Hangzhou Juno Genomics, Inc
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PM2_Supporting+PS3+PM3_Strong+PP4_Moderate -

Oct 17, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 252 of the PAH protein (p.Arg252Gln). This variant is present in population databases (rs62644503, gnomAD 0.005%). This missense change has been observed in individuals with phenylketonuria (PMID: 7833954, 16256386, 23430547, 24401910, 30050108). ClinVar contains an entry for this variant (Variation ID: 102824). 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 PAH protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects PAH function (PMID: 11243094, 17924342, 21953985). This variant disrupts the p.Arg252 amino acid residue in PAH. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 2574153, 8116675, 12655546, 17096675, 20082265, 25596310). 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. -

Mar 01, 2024
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 30, 2021
Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PAH NM_000277.2 exon 7 p.Arg252Gln (c.755G>A): This variant has been reported in the literature as a compound heterozygote in at least 1 individual with PKU (Benit 1994 PMID:7833954) and has been reported in the BIOPKU database (http://www.biopku.org). This variant is present in 0.005% (1/19948) of East Asian alleles in the Genome Aggregation Database (http://gnomad.broadinstitute.org/variant/12-103246680-C-T). Please note, disease causing variants may be present in control databases at low frequencies, reflective of the general population, carrier status and/or variable expressivity. This variant is present in ClinVar (Variation ID:102824). Evolutionary conservation and computational predictive tools suggest that this variant may impact the protein. Of note, computational tools designed to predict splicing suggest a potential effect from this variant. However, further studies are needed to understand its impact. Functional studies support a deleterious effect of this variant, suggesting decreased protein production or activity compared to wild-type (Bjorgo 1998 PMID:9799096, Shi 2012 PMID:21953985, Himmelreich 2018 PMID:30037505). Furthermore, other variants at this same codon (p.Arg252Pro, p.Arg252Trp, p.Arg252Gly) have been reported in the literature, with at least one of these variants with sufficient evidence for association with disease. In summary, data on this variant is highly suspicious for disease, but requires further evidence for pathogenicity. Therefore, this variant is classified as likely pathogenic. -

Sep 16, 2020
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Pathogenic:3Other:1
Sep 28, 2022
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported in an individual with PKU who harbored a second PAH variant (Benit et al., 1994); Functional analysis demonstrates decreased PAH enzyme activity (Liang et al., 2014); 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); In silico analysis suggests this variant may impact gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; This variant is associated with the following publications: (PMID: 21228398, 30747360, 21953985, 7833954, 8188310, 24401910, 27264808, 9634518, 11243094, 30037505, 30275481, 34426522, 31589614, 32668217, 32778825) -

-
DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Apr 28, 2015
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Apr 27, 2021
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The variant is associated with classic PKU in the published literature (PMID: 9634518 (1998), 24401910 (2014)). Assessment of experimental evidence regarding the effect of this variant suggests it disrupts normal PAH enzymatic activity (PMID: 24401910 (2014), 21953985 (2012), 11243094 (1997)). Therefore, the variant is classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.89
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.99
D;D
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.93
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D
M_CAP
Pathogenic
0.45
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.1
M;.
PrimateAI
Uncertain
0.77
T
PROVEAN
Uncertain
-3.8
D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;D
Sift4G
Uncertain
0.0020
D;D
Polyphen
1.0
D;.
Vest4
0.85
MutPred
0.96
Loss of methylation at R252 (P = 0.0335);.;
MVP
0.99
MPC
0.25
ClinPred
1.0
D
GERP RS
5.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
gMVP
0.94

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.11
Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs62644503; hg19: chr12-103246680; API