NM_000277.3:c.187A>C

Variant names:

• chr12-102894900-T-G
• rs199475568
• NM_000277.3:c.187A>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PP4_Moderate PM2

This summary comes from the ClinGen Evidence Repository: The c.187A>C (p.Thr63Pro) variant in PAH was detected in 1 Danish PKU patient (Phenylalanine > 600 umol/L). Other causes of hyperphenylalaninemia had been ruled out. (PMID:8406445). It was in cis with a p.H64N variant (No assertion provided, ClinVar). The c.187A>C variant is absent from ExAC, gnomAD, 1000G, and ESP. There are conflicting predictions of pathogenicity: SIFT:T,D; Polyphen2:D,P; MutationTaster:Disease causing; REVEL:0.768. In summary, this variant meets criteria to be classified as uncertain significance for PAH. PAH-specific ACMG/AMP criteria applied: PM2, PP4_Moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CA229473/MONDO:0009861/006

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Uncertain significance reviewed by expert panel P:1 U:1 O:1
• Conservation: PhyloP100: 7.13
• Publications: 5 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):

• 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

LOC124902999 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

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

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAH	NM_000277.3	MANE Select	c.187A>C	p.Thr63Pro	missense	Exon 3 of 13	NP_000268.1
	PAH	NM_001354304.2		c.187A>C	p.Thr63Pro	missense	Exon 4 of 14	NP_001341233.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAH	ENST00000553106.6	TSL:1 MANE Select	c.187A>C	p.Thr63Pro	missense	Exon 3 of 13	ENSP00000448059.1
	PAH	ENST00000549111.5	TSL:1	n.283A>C		non_coding_transcript_exon	Exon 3 of 6
	PAH	ENST00000307000.7	TSL:5	c.172A>C	p.Thr58Pro	missense	Exon 4 of 14	ENSP00000303500.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461278 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726992

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53202

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111672

Other (OTH) AF: 0.00 AC: 0 AN: 60364

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

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

Revision: reviewed by expert panel

Submissions by phenotype

not provided Pathogenic:1 Other:1

Nov 30, 2018

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed in large population cohorts (Lek et al., 2016); Missense variants in this gene are often considered pathogenic (Stenson et al., 2014); 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: 32668217, 11161839, 30037505)

DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Phenylketonuria Uncertain:1

Dec 10, 2018

ClinGen PAH Variant Curation Expert Panel

Significance: Uncertain significance

Review Status: reviewed by expert panel

Collection Method: curation

The c.187A>C (p.Thr63Pro) variant in PAH was detected in 1 Danish PKU patient (Phenylalanine > 600 umol/L). Other causes of hyperphenylalaninemia had been ruled out. (PMID: 8406445). It was in cis with a p.H64N variant (No assertion provided, ClinVar). The c.187A>C variant is absent from ExAC, gnomAD, 1000G, and ESP. There are conflicting predictions of pathogenicity: SIFT:T,D; Polyphen2:D,P; MutationTaster:Disease causing; REVEL:0.768. In summary, this variant meets criteria to be classified as uncertain significance for PAH. PAH-specific ACMG/AMP criteria applied: PM2, PP4_Moderate.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.55
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.44	D
MetaRNN	Pathogenic	0.85	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.5	H
PhyloP100		7.1
PrimateAI	Uncertain	0.71	T
PROVEAN	Uncertain	-3.3	D
REVEL	Pathogenic	0.77
Sift	Benign	0.22	T
Sift4G	Benign	0.28	T
Polyphen		0.94	P
Vest4		0.79
MutPred		0.48		Loss of stability (P = 0.0496)
MVP		0.98
MPC		0.18
ClinPred		1.0	D
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.96
gMVP		0.91
Mutation Taster		=11/89	disease causing

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

Other links and lift over

dbSNP: rs199475568; hg19: chr12-103288678;