rs199475579

Positions:

• chr12-102852917-C-A
• chr12-102852917-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000277.3(PAH):​c.740G>T​(p.Gly247Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,854 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G247D) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6 O: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]

PAH (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a strand (size 2) in uniprot entity PH4H_HUMAN there are 8 pathogenic changes around while only 0 benign (100%) 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 chr12-102852917-C-T is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 12-102852917-C-A is Pathogenic according to our data. Variant chr12-102852917-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 102818.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr12-102852917-C-A is described in Lovd as [Pathogenic]. Variant chr12-102852917-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PAH	NM_000277.3	c.740G>T	p.Gly247Val	missense_variant	7/13	ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.740G>T	p.Gly247Val	missense_variant	8/14		NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.740G>T	p.Gly247Val	missense_variant	7/13	1	NM_000277.3	ENSP00000448059.1
PAH	ENST00000307000.7	c.725G>T	p.Gly242Val	missense_variant	8/14	5		ENSP00000303500.2
PAH	ENST00000549247.6	n.499G>T		non_coding_transcript_exon_variant	1/6	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461854 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727226

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Phenylketonuria Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Juno Genomics, Hangzhou Juno Genomics, Inc	-	PM2_Supporting+PP3_Strong+PM3_VeryStrong -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Aug 29, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jan 10, 2020	Variant summary: PAH c.740G>T (p.Gly247Val) results in a non-conservative amino acid change located in the Aromatic amino acid hydroxylase, C-terminal (IPR019774) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251220 control chromosomes. c.740G>T has been frequently reported in the literature in multiple individuals affected with Phenylalanine Hydroxylase Deficiency (Phenylketonuria) (example, 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 <10% of normal activity reporting a functionally hemizygous genotype in combination with null mutations (Li_2018). Two 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. -
Likely pathogenic, criteria provided, single submitter	literature only	Counsyl	Oct 14, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 15, 2023	This sequence change replaces glycine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 247 of the PAH protein (p.Gly247Val). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with phenylketonuria (PMID: 26600521). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 102818). 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 expected to disrupt PAH protein function. Experimental studies have shown that this missense change affects PAH function (PMID: 17924342, 21953985). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Nov 13, 2017	- -
not provided, no classification provided	literature only	DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE	-	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	1.0	D;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D
M_CAP	Pathogenic	0.60	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Pathogenic	4.7	H;.
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-8.6	D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.98
MutPred		0.99		Loss of methylation at R243 (P = 0.1231);.;
MVP		0.99
MPC		0.26
ClinPred		1.0	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		0.99

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: rs199475579; hg19: chr12-103246695;