12-102843645-C-T

Position:

• chr12-102843645-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PP4 PVS1 PM2

This summary comes from the ClinGen Evidence Repository: This c.1199+1G>A variant in PAH was reported in 1 Czech patient with PAH deficiency (PMID:23357515), although a defect in BH4 metabolism was not excluded. This variant is present in European (non-Finnish) populations at an extremely low frequency in gnomAD (MAF: 0.00001). This variant in the +1 splice donor site results in exon skipping, which disrupts the reading frame and is predicted to undergo nonsense mediated decay. The exon is present in biologically-relevant transcripts. In summary, this variant meets criteria to be classified as pathogenic for PAH. PAH-specific ACMG/AMP criteria applied: PVS1, PM2, PP4. LINK:https://erepo.genome.network/evrepo/ui/classification/CA229385/MONDO:0009861/006

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PAH NM_000277.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic reviewed by expert panel P:5 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 11 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: 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.1199+1G>A		splice_donor_variant, intron_variant		ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.1199+1G>A		splice_donor_variant, intron_variant			NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.1199+1G>A		splice_donor_variant, intron_variant		1	NM_000277.3	ENSP00000448059.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251270 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135804

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461494 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727050

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Phenylketonuria Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 26, 2023	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jul 18, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 25, 2022	For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 102556). Disruption of this splice site has been observed in individual(s) with phenylketonuria (PMID: 9634518, 30159852; Invitae). This variant is present in population databases (rs62509015, gnomAD 0.0009%). This sequence change affects a donor splice site in intron 11 of the PAH gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in PAH are known to be pathogenic (PMID: 1301187, 9634518). -
Pathogenic, reviewed by expert panel	curation	ClinGen PAH Variant Curation Expert Panel	Oct 15, 2020	This c.1199+1G>A variant in PAH was reported in 1 Czech patient with PAH deficiency (PMID: 23357515), although a defect in BH4 metabolism was not excluded. This variant is present in European (non-Finnish) populations at an extremely low frequency in gnomAD (MAF: 0.00001). This variant in the +1 splice donor site results in exon skipping, which disrupts the reading frame and is predicted to undergo nonsense mediated decay. The exon is present in biologically-relevant transcripts. In summary, this variant meets criteria to be classified as pathogenic for PAH. PAH-specific ACMG/AMP criteria applied: PVS1, PM2, PP4. -

not provided Other:1

not provided, no classification provided

literature only

DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.99
FATHMM_MKL	Pathogenic	1.0	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.64		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.52		Position offset: -16
DS_DL_spliceai		0.64		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs62509015; hg19: chr12-103237423;