12-102852923-A-G

Position:

• chr12-102852923-A-G

Variant summary

Our verdict is Pathogenic. Variant got 6 ACMG points: 6P and 0B. PM3 PM5 PP4_Moderate

This summary comes from the ClinGen Evidence Repository: PAH-specific ACMG/AMP criteria applied: PM5: V245L Pathogenic; PP4_Moderate: Seen in at least 7 MHP patients. Exclusion of a defect in tetrahydrobiopterin metabolism. Upgraded per ClinGen Metabolic Workgroup. (PMID:7981714; PMID:9298832; PMID:9634518); PM3_VeryStrong: V245A detected with IVS-12nt1, R252W, L194P (both P/LP), R408W (Path). Upgraded per ClinGen SVI Workgroup (PMID:7981714; PMID:9298832; PMID:8088845). 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: (PM5, PP4_Moderate, PM3_VeryStrong). LINK:https://erepo.genome.network/evrepo/ui/classification/CA114372/MONDO:0009861/006

• Frequency:
  • Genomes: 𝑓 0.00047 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00054 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:20 U:1 O:1
• Conservation: PhyloP100: 9.32

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]

ACMG classification

Verdict is Pathogenic. Variant got 6 ACMG points.

• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PM5: 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/exons	MANE	Protein	UniProt
PAH	NM_000277.3	c.734T>C	p.Val245Ala	missense_variant	7/13	ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.734T>C	p.Val245Ala	missense_variant	8/14		NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.734T>C	p.Val245Ala	missense_variant	7/13	1	NM_000277.3	ENSP00000448059	P1
PAH	ENST00000307000.7	c.719T>C	p.Val240Ala	missense_variant	8/14	5		ENSP00000303500
PAH	ENST00000549247.6	n.493T>C		non_coding_transcript_exon_variant	1/6	2

Frequencies

GnomAD3 genomes AF: 0.000467 AC: 71 AN: 152182 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.0000941

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000941

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000482 AC: 121 AN: 251208 Hom.: 0 AF XY: 0.000552 AC XY: 75 AN XY: 135754

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.000318

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.000916

Gnomad OTH exome AF: 0.000489

GnomAD4 exome AF: 0.000544 AC: 795 AN: 1461842 Hom.: 0 Cov.: 32 AF XY: 0.000521 AC XY: 379 AN XY: 727220

Gnomad4 AFR exome AF: 0.000149

Gnomad4 AMR exome AF: 0.000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000749

Gnomad4 NFE exome AF: 0.000662

Gnomad4 OTH exome AF: 0.000497

GnomAD4 genome AF: 0.000466 AC: 71 AN: 152300 Hom.: 0 Cov.: 32 AF XY: 0.000443 AC XY: 33 AN XY: 74458

Gnomad4 AFR AF: 0.0000962

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.0000941

Gnomad4 NFE AF: 0.000941

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000610 Hom.: 0

Bravo AF: 0.000495

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.000778 AC: 3

ESP6500AA AF: 0.000227 AC: 1

ESP6500EA AF: 0.000698 AC: 6

ExAC AF: 0.000708 AC: 86

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:20 Uncertain:1 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Phenylketonuria Pathogenic:12

Pathogenic, reviewed by expert panel	curation	ClinGen PAH Variant Curation Expert Panel	Sep 28, 2018	PAH-specific ACMG/AMP criteria applied: PM5: V245L Pathogenic; PP4_Moderate: Seen in at least 7 MHP patients. Exclusion of a defect in tetrahydrobiopterin metabolism. Upgraded per ClinGen Metabolic Workgroup. (PMID:7981714; PMID:9298832; PMID:9634518); PM3_VeryStrong: V245A detected with IVS-12nt1, R252W, L194P (both P/LP), R408W (Path). Upgraded per ClinGen SVI Workgroup (PMID:7981714; PMID:9298832; PMID:8088845). 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: (PM5, PP4_Moderate, PM3_VeryStrong). -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Dec 17, 2019	NM_000277.1(PAH):c.734T>C(V245A) is classified as pathogenic in the context of phenylalanine hydroxylase deficiency and can be associated with variant or non-PKU HPA. Sources cited for classification include the following: PMID 10394930, 16198137, 24350308, 11161839, 16198137, 9781015, 12655553, 23764561, 8088845 and 12501224. Classification of NM_000277.1(PAH):c.734T>C(V245A) is based on the following criteria: This is a well-established pathogenic variant in the literature that has been observed more frequently in patients with clinical diagnoses than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 29, 2024	This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 245 of the PAH protein (p.Val245Ala). This variant is present in population databases (rs76212747, gnomAD 0.09%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with hyperphenylalaninaemia (PMID: 8088845, 24296287, 25596310, 26803807). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 632). 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 PAH protein function with a negative predictive value of 80%. Experimental studies have shown that this missense change affects PAH function (PMID: 26803807). This variant disrupts the p.Val245 amino acid residue in PAH. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 11161839, 15159646). 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. -
Likely pathogenic, no assertion criteria provided	research	Division of Human Genetics, Children's Hospital of Philadelphia	Mar 16, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Mar 09, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Oct 31, 2018	The PAHc.734T>C (p.Val245Ala) missense variant has been reported in four studies in which it is identified in a compound heterozygous state in a total of eight individuals with phenylalanine hydroxylase deficiency (Gulberg et al. 1994; Zekanowski et al 1997; Kasnauskiene et al. 2003; Trunzo et al. 2014). The p.Val245Ala variant was absent from 220 control chromosomes and is reported at a frequency of 0.00114 in the European (non-Finnish) population of the Exome Aggregation Consortium. Danecka et al. (2015) provided functional assessment of a variety of PAH variants co-expressed in COS-7 cells, and demonstrated reduced activity of the p.Val245Ala variant as compared to wild type. Based on the collective evidence, the p.Val245Ala variant is classified as pathogenic for phenylalanine hydroxylase deficiency. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
Pathogenic, criteria provided, single submitter	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	Oct 08, 2014	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 27, 2024	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Apr 22, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Dec 21, 2023	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with phenylketonuria (MIM#261600). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from valine to alanine. (I) 0251 - Variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (130 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (6 heterozygotes, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated biopterin H domain (DECIPHER). (I) 0703 - Other missense variants comparable to the one identified in this case have moderate previous evidence for pathogenicity. Alternative changes p.(Val245Leu) and p.(Val245Glu) have been reported as pathogenic in patients with phenylketonuria (ClinVar). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been reported multiple times in patients with mild phenylketonuria (ClinVar, PMID: 26666653). (SP) 1208 - Inheritance information for this variant is not currently available. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

not provided Pathogenic:5 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	May 16, 2022	Published functional studies demonstrate V245A is associated with residual phenylalanine hydroxylase enzyme activity (Zurfluh et al., 2008; Heintz et al., 2013; Danecka et al., 2015); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 26666653, 24939588, 8739972, 10980574, 23559577, 25596310, 8088845, 17935162, 16601866, 25087612, 24055113, 24296287, 25637381, 12640344, 7981714, 9298832, 9781015, 8533759, 26803807, 26990548, 31980526, 33326653, 31589614, 32668217, 32778825) -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jul 05, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jul 02, 2015	- -
not provided, no classification provided	literature only	DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE	-	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics Laboratory, Skane University Hospital Lund	May 27, 2022	- -

Hyperphenylalaninemia Pathogenic:2 Uncertain:1

Uncertain significance, no assertion criteria provided	research	CSER _CC_NCGL, University of Washington	Jun 01, 2014	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	May 15, 1994	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Apr 13, 2017	Variant summary: The PAH c.734T>C (p.Val245Ala) variant involves the alteration of a conserved nucleotide. 4/5 in silico tools predict a damaging outcome for this variant. This variant was found in 86/121256 control chromosomes at a frequency of 0.0007092, which does not exceed the estimated maximal expected allele frequency of a pathogenic PAH variant (0.0079057). This variant has been reported in many HPA alleles worldwide and functional studies showed variant with ~ 50% residue activity, which explains the mild phenotype of patients with this variant. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 21, 2021

The c.734T>C (p.V245A) alteration is located in exon 7 (coding exon 7) of the PAH gene. This alteration results from a T to C substitution at nucleotide position 734, causing the valine (V) at amino acid position 245 to be replaced by an alanine (A). Based on data from the Genome Aggregation Database (gnomAD) database, the PAH c.734T>C alteration was observed in 0.05% (130/282610) of total alleles studied, with a frequency of 0.09% (112/128966) in the European (non-Finnish) subpopulation. This common mutation and has been detected in combination with a second variant in many individuals affected with nonphenylketonuria hyperphenylalaninemia and mild hyperphenylalaninemia (Guldberg, 1994; Aldámiz-Echevarría, 2016; Tolve, 2018). This amino acid position is completely conserved on sequence alignment. In vitro functional studies have shown that this alteration impairs PAH (phenylalanine hydroxylase) activity (Shen, 2016; Danecka, 2015). The p.V245A alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Pathogenic	0.53
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;D
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Uncertain	0.28	D
MetaRNN	Uncertain	0.66	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	2.9	M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-3.8	D;D
REVEL	Pathogenic	0.90
Sift	Benign	0.12	T;T
Sift4G	Benign	0.20	T;T
Polyphen		1.0	D;.
Vest4		0.89
MVP		0.95
MPC		0.26
ClinPred		0.18	T
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.78
gMVP		0.97

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

LitVar

Other links and lift over

dbSNP: rs76212747; hg19: chr12-103246701;