rs5030849

chr12-102852875-C-Achr12-102852875-C-Gchr12-102852875-C-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_000277.3(PAH):c.782G>T(p.Arg261Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R261G) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Uncertain significance reviewed by expert panel P:1 U:1
• Conservation: PhyloP100: 7.91

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 10 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000277.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-102852875-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 102832.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PAH	NM_000277.3	c.782G>T	p.Arg261Leu	missense_variant	7/13	ENST00000553106.6
PAH	NM_001354304.2	c.782G>T	p.Arg261Leu	missense_variant	8/14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PAH	ENST00000553106.6	c.782G>T	p.Arg261Leu	missense_variant	7/13	1	NM_000277.3	P1
PAH	ENST00000307000.7	c.767G>T	p.Arg256Leu	missense_variant	8/14	5
PAH	ENST00000549247.6	n.541G>T		non_coding_transcript_exon_variant	1/6	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Phenylketonuria Pathogenic:1 Uncertain:1

Uncertain significance, reviewed by expert panel	curation	ClinGen PAH Variant Curation Expert Panel	Nov 08, 2019	The c.782G>T (p.Arg261Leu) variant in PAH has been previously reported Pathogenic by one clinical laboratory in ClinVar (see variant ID 576255); the laboratory stated that it was found as an "inherited" allele in 1 Han Chinese proband with PKU (subtype not otherwise specified, no further phenotypic details given). No further information regarding zygosity, familial segregation, and/or functional assays was provided, and no formal classification criteria were given, aside from "case-control" was given in the collection method. The variant results in a substitution of a highly conserved Arg residue with Leucine; the two amino acid residues are physiochemically distinct (basic versus nonpolar side chains) and the substitution is predicted damaging by multiple lines of computational evidence, e.g., Predicted deleterious in SIFT, Polyphen2, Mutation Taster. REVEL= 0.979) (PP3). It is absent from control databases including ethnically matched individuals, including gnomAD/ExAC, 1000 Genomes, and ESP (PM2). [Although there is frequency data retrieved for it in the PAGE/GGV browser in the ClinGen VCI, when the genomic coordinates for it are entered into the browser, nothing comes up]. Other missense changes at this Arg (Arg261) have been previously reported Pathogenic or Likely Pathogenic in ClinVar, e.g., p.Arg261Gln (Pathogenic per internal PAH ClinGen Working Group classification, ClinVar ID 582), as well as p.Arg261Gly and p.Arg261Pro (PM5). -
Pathogenic, no assertion criteria provided	case-control	Clinical Laboratory, Xuzhou Maternity and Child Health Care Hospital	Jun 26, 2018	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
Cadd	Pathogenic	32
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	1.0	D;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.99
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	4.3	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-6.6	D;D
REVEL	Pathogenic	0.98
Sift	Uncertain	0.0010	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.96
MutPred		0.90		Loss of methylation at R261 (P = 0.0162);.;
MVP		0.99
MPC		0.26
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.97
gMVP		0.98

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: rs5030849; hg19: chr12-103246653;