chr12-102855331-C-G

Variant names:

• chr12-102855331-C-G
• NM_000277.3:c.511G>C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3 PP5_Moderate

The NM_000277.3(PAH):​c.511G>C​(p.Gly171Arg) variant causes a missense, splice region 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. 14/23 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G171A) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PAH NM_000277.3 missense, splice_region
• Scores: Splicing: ADA: 0.9683
• Clinical Significance: Pathogenic criteria provided, single submitter P: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 Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a strand (size 2) in uniprot entity PH4H_HUMAN there are 9 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 chrnull-null-null-null is described in UniProt as null.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
• PP5: Variant 12-102855331-C-G is Pathogenic according to our data. Variant chr12-102855331-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 1384858.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr12-102855331-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PAH	NM_000277.3	c.511G>C	p.Gly171Arg	missense_variant, splice_region_variant	Exon 6 of 13	ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.511G>C	p.Gly171Arg	missense_variant, splice_region_variant	Exon 7 of 14		NP_001341233.1
PAH	XM_017019370.2	c.511G>C	p.Gly171Arg	missense_variant, splice_region_variant	Exon 6 of 7		XP_016874859.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.511G>C	p.Gly171Arg	missense_variant, splice_region_variant	Exon 6 of 13	1	NM_000277.3	ENSP00000448059.1
PAH	ENST00000549111.5	n.607G>C		splice_region_variant, non_coding_transcript_exon_variant	Exon 6 of 6	1
PAH	ENST00000307000.7	c.496G>C	p.Gly166Arg	missense_variant, splice_region_variant	Exon 7 of 14	5		ENSP00000303500.2
PAH	ENST00000551988.5	n.532G>C		splice_region_variant, non_coding_transcript_exon_variant	Exon 5 of 5	3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Phenylketonuria Pathogenic:1

May 28, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Available"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Not Available"). ClinVar contains an entry for this variant (Variation ID: 1384858). This missense change has been observed in individual(s) with PAH-related conditions (PMID: 26600521, 28982351, 30626930; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 171 of the PAH protein (p.Gly171Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	1.0	D;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.97
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.65	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	4.1	H;.
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-7.8	D;D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.84
MutPred		0.92		Gain of solvent accessibility (P = 0.0037);.;
MVP		1.0
MPC		0.25
ClinPred		1.0	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.94
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Pathogenic	0.92
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr12-103249109;