NM_000277.3:c.755G>A

Variant names:

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PP3PM3PS3PP4_ModeratePM2

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

Clinical Significance

Pathogenic reviewed by expert panel P:12O:1

Conservation

PhyloP100: 7.91

Publications

33 publications found

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]

PAH Gene-Disease associations (from GenCC):

phenylketonuria
Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Myriad Women’s Health
classic phenylketonuria
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
maternal phenylketonuria
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
mild hyperphenylalaninemia
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
mild phenylketonuria
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

PAH links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 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
PAH	NM_000277.3 link	c.755G>A	p.Arg252Gln	missense_variant	Exon 7 of 13	ENST00000553106.6	NP_000268.1	P00439A0A024RBG4
PAH	NM_001354304.2 link	c.755G>A	p.Arg252Gln	missense_variant	Exon 8 of 14		NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
PAH	ENST00000553106.6 link	c.755G>A	p.Arg252Gln	missense_variant	Exon 7 of 13	1	NM_000277.3	ENSP00000448059.1	P00439
PAH	ENST00000307000.7 link	c.740G>A	p.Arg247Gln	missense_variant	Exon 8 of 14	5		ENSP00000303500.2	J3KND8
PAH	ENST00000549247.6 link	n.514G>A		non_coding_transcript_exon_variant	Exon 1 of 6	2
PAH	ENST00000635477.1 link	c.-86G>A		upstream_gene_variant		5		ENSP00000489230.1	A0A0U1RQY4

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

152030

Hom.:

Cov.:

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

GnomAD2 exomes

AF:

0.00000796

AC:

AN:

251262

AF XY:

0.00000736

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 FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000616

AC:

AN:

1461852

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

727228

show subpopulations

African (AFR)

AF:

0.0000299

AC:

AN:

33478

American (AMR)

AF:

0.00

AC:

AN:

44722

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.0000504

AC:

AN:

39696

South Asian (SAS)

AF:

0.0000348

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53414

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00000270

AC:

AN:

1111988

Other (OTH)

AF:

0.00

AC:

AN:

60392

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.492

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000132

AC:

AN:

152030

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74244

show subpopulations

African (AFR)

AF:

0.0000242

AC:

AN:

41370

American (AMR)

AF:

0.00

AC:

AN:

15272

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5186

South Asian (SAS)

AF:

0.00

AC:

AN:

4818

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10588

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68012

Other (OTH)

AF:

0.00

AC:

AN:

2084

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.650

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000106

Hom.:

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

Sep 16, 2020

Natera, Inc.

Significance:Pathogenic

Review Status:no assertion criteria provided

Collection Method:clinical testing

- -

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 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 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. -

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). -

Mar 01, 2024

Baylor Genetics

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

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 -

not provided

Pathogenic:3Other:1

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. -

DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE

Significance:not provided

Review Status:no classification provided

Collection Method:literature only

- -

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) -

Apr 28, 2015

Eurofins Ntd Llc (ga)

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.89

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.58

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.99

D;D

Eigen

Pathogenic

0.96

Eigen_PC

Pathogenic

0.93

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

1.0

D;D

M_CAP

Pathogenic

0.45

MetaRNN

Pathogenic

0.99

D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.1

M;.

PhyloP100

7.9

PrimateAI

Uncertain

0.77

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

GERP RS

5.9

PromoterAI

-0.030

Neutral

(source)

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.96

gMVP

0.94

Mutation Taster

=5/95

disease causing (ClinVar)

(source)

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

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Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over