12-102855313-C-G

Variant names:

• chr12-102855313-C-G
• rs199475602
• NM_000277.3:c.529G>C
• PAH p.Val177Leu

GermlineCancer (beta)

Variant summary

Our verdict is Likely pathogenic.

+7 Likely Pathogenic

-7

-6

-1

0

+5

+6

+9

+10

BenignB

Likely BenignLB

UncertainVUS

Likely PathogenicLP

PathogenicP

The variant received 7 classification points (ACGS-UK Somatic Oncogenicity v2025). O1_ModerateO3_SupportingO5_SupportingO6_SupportingO7_SupportingO8_Supporting

The NM_000277.3(PAH):c.529G>C (p.Val177Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The gene PAH is a tumor suppressor gene (CancerMine: 1 TSG citations). The variant allele was found at a cumulative frequency of 0.00000929 (AC=15) in the gnomAD database across 1,613,972 control chromosomes (no homozygotes observed). The grpmax filtering allele frequency (95% CI) is 0.0000117. In-silico predictor (REVEL) classifies this variant as likely damaging/oncogenic. Splicing prediction tools (SpliceAI) predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic/Likely Pathogenic (★★★). A different missense at the same amino acid position has been reported as Pathogenic/Likely Pathogenic in ClinVar: p.V177A: Likely_pathogenic (ClinVar VariationId 4710022, 1 star) This exact variant is curated in the UniProt human variants database as Uncertain Significance.

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:10 O:1
• Conservation: PhyloP100: 3.39
• Publications: 6 publications found

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):

• classic phenylketonuria

  Inheritance: AR Classification: DEFINITIVE Submitted by: Natera
• phenylketonuria

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, G2P, ClinGen, Labcorp Genetics (formerly Invitae), Myriad Women's Health
• maternal phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mild hyperphenylalaninemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Classification according to ACGS-UK Somatic Oncogenicity v2025

Specifications for PAH are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Classification was made for transcript:

Our verdict: Likely_pathogenic. The variant received 7 points.

Apply	Criterion Code & Title / Strength	Strength	Rationale / Clinical Context
	O1Established oncogenic variant		TSG gene: ClinVar germline P/LP ★★+ — Moderate (O1); O1 contributing sources (2.0 pts): ClinVar germline P/LP in TSG (★★★)
	O3Absent or very rare in population		Very rare in gnomAD (popmax AF <0.01%) — O3 supporting; GnomAD effective popmax AF = 0.000012 — very rare (O3 supporting [+1])
	O5Same location/impact as known oncogenic		Different AA at same residue with oncogenic evidence (or germline P/LP in TSG), or same AA change SCI Tier II Potential — Supporting (O5); ClinVar same-AA oncogenic/T1: false | ClinVar same-AA SCI tier: — | CGI same-AA oncogenic: false | TSG: true | ClinVar same-AA germline P/LP: false | CIViC LOF: false | ClinVar diff-AA oncogenic: false | ClinVar diff-AA germline P/LP: true
	O6Computational evidence supports deleterious effect		Computational evidence supports a deleterious/oncogenic effect; Missense variant — primary computational scorer supports an oncogenic/deleterious effect
	O7Mutational hotspot or critical domain		Supporting: cancerhotspots.org hit, critical domain, or missense neighbourhood hotspot; No cancerhotspots.org hit at this position; UniProt domain: 0 pathogenic, 0 benign.; ±8 AA neighbourhood: 35 pathogenic, 0 benign (OR vs. background: 355.0); Variant does not impact splicing — splice-hotspot path not applicable
	O8Missense constraint in gene or region		Missense in gene/domain constrained for missense variation where missense is common disease mechanism (O8 supporting); Gene/disease mechanism: missense is a common mechanism of oncogenesis; gnomAD missense Z-score: -0.00 (threshold ≥3.09 for constraint); Domain-level constraint: variant is in a critically constrained functional domain (IS_AT_CRITICAL_DOMAIN)

Variant Effect in Transcripts

Automated classification analysis was done for transcript: NM_000277.3. You can select a different transcript below to see updated classification assignments.

RefSeq Transcripts

Sel.	Gene / Transcript	Tags	HGVSc / HGVSp	Effect	Exon rank	Protein / UniProt
	PAH NM_000277.3	MANE Select	c.529G>C p.Val177Leu	missense	Exon 6 of 13	Prot: NP_000268.1 UniProt:
	PAH NM_001354304.2		c.529G>C p.Val177Leu	missense	Exon 7 of 14	Prot: NP_001341233.1 UniProt:

PAH NM_000277.3

MANE Select

HGVSc / HGVSpc.529G>Cp.Val177Leu

Exon rankExon 6 of 13

missense

Prot: NP_000268.1UniProt: P00439

PAH NM_001354304.2

HGVSc / HGVSpc.529G>Cp.Val177Leu

Exon rankExon 7 of 14

missense

Prot: NP_001341233.1UniProt: P00439

Ensembl Transcripts

Sel.	Gene / Transcript	Tags	HGVSc / HGVSp	Effect	Exon rank	Protein / UniProt
	PAH ENST00000553106.6	TSL:1MANE Select	c.529G>C p.Val177Leu	missense	Exon 6 of 13	Prot: ENSP00000448059.1 UniProt:
	PAH ENST00000549111.5	TSL:1	n.625G>C	non_coding_transcript_exon	Exon 6 of 6	Prot:
	PAH ENST00000906695.1		c.529G>C p.Val177Leu	missense	Exon 6 of 14	Prot: ENSP00000576754.1 UniProt:

PAH ENST00000553106.6

TSL:1MANE Select

HGVSc / HGVSpc.529G>Cp.Val177Leu

Exon rankExon 6 of 13

missense

Prot: ENSP00000448059.1UniProt: P00439

PAH ENST00000549111.5

TSL:1

HGVSc / HGVSpn.625G>C

Exon rankExon 6 of 6

non_coding_transcript_exon

Prot:

PAH ENST00000906695.1

HGVSc / HGVSpc.529G>Cp.Val177Leu

Exon rankExon 6 of 14

missense

Prot: ENSP00000576754.1UniProt: A0ACI8RXH2

Frequencies

Allele frequencies (AF), counts (AC/AN), homozygotes and coverage

Common (AF > 0.05 / Hom > 5)

Rare (AF ≤ 0.0001 / Hom ≤ 1)

Source / population	AF	AC	Hom	AN	Coverage
Global population databases 6 sources Large-scale international reference populations
GnomAD3 genomes	AF: 0.0000197	AC:3	Hom:0	AN:152142	Cov:33
GnomAD2 exomes	AF: 0.0000199	AC:5	Hom:	AN:251188	Cov:
GnomAD4 exome	AF: 0.00000821	AC:12	Hom:0	AN:1461830	Cov:34
GnomAD4 genome	AF: 0.0000197	AC:3	Hom:0	AN:152142	Cov:33
TOPMed (Bravo)	AF: 0.0000113	AC:	Hom:	AN:	Cov:
ALFA (dbGaP/dbSNP Allele Frequency Aggregator)	AF: 0.00	AC:0	Hom:0	AN:44616	Cov:
Local & regional cohorts 1 source Population-specific and national genomic databases
ESP6500 (Exome Variant Server)	AF: 0.0000769	AC:1	Hom:	AN:13006	Cov:

Showing 7 sources

Case/control cohorts

Cohort	Cases			Controls
	AF	AC	AN	AF	AC	AN
Epi25(Epilepsy)	0.0000477	2	41958	0.00	0	66888
SCHEMA(Schizophrenia)	0.00	0	67736	0.00000752	1	132966

Showing 2 cohortsAllele count / allele number. AF is computed from the counts for ASC (not provided by the source).

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
7	-	-	Phenylketonuria (7)
2	-	-	not provided (3)
1	-	-	PAH-related disorder (1)

Computational Scores

Algorithm	Calibrated pred.	Score	Prediction
AlphaGenome AVI	Pathogenic	24
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Pathogenic	0.28
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.96	D
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Pathogenic	0.99	D
FuncVEP CTI	Pathogenic	0.55
GPN-Star LLR	N/A	-6.5
GPN-Star score	N/A	6.5
LIST_S2	Uncertain	0.93	D
M_CAP	Pathogenic	0.45	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Pathogenic	1.0	D
Mutation Taster	N/A	13/87	disease causing (ClinVar)
MutationAssessor	Pathogenic	3.2	M
PhyloP100	Benign	3.4
popEVE	Benign	-3.1
PrimateAI	Uncertain	0.58	T
PROVEAN	Uncertain	-2.4	N
RBP_binding_hub_radar	N/A	0.0
RBP_regulation_power_radar	N/A	1.1
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0050	D
Sift4G	Uncertain	0.021	D
Varity_R	N/A	0.86
VESM-3B	Benign	-7.7

Showing 30 of 30 scores

Splicing Scores

Algorithm	Calibrated pred.	Score	Prediction
Pangolin (max)	Benign	0.0
SpliceAI score (max)	Benign	0.0	Details are displayed if max score is > 0.2

Showing 2 of 2 scores

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

MaveDB functional evidence

MaveDB is a public repository of laboratory assays that test the effect of thousands of variants at once — treat this as supporting research data and interpret it with great caution; it is not a clinical classification.

No MaveDB functional evidence found for this variant.

Other links and lift over

dbSNP: rs199475602;

hg19: chr12-103249091;

ACMG debug oncogenicity

ACGS debug oncogenicity

ACMG debug germline

Submit to ClinVar