rs199475615

Positions:

• chr12-102846904-C-G

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000277.3(PAH):​c.960G>C​(p.Lys320Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,302 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5 O:1
• Conservation: PhyloP100: 0.894

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 16 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 12 uncertain in NM_000277.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985
• PP5: Variant 12-102846904-C-G is Pathogenic according to our data. Variant chr12-102846904-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 102910.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr12-102846904-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PAH	NM_000277.3	c.960G>C	p.Lys320Asn	missense_variant	9/13	ENST00000553106.6
PAH	NM_001354304.2	c.960G>C	p.Lys320Asn	missense_variant	10/14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PAH	ENST00000553106.6	c.960G>C	p.Lys320Asn	missense_variant	9/13	1	NM_000277.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461302 Hom.: 0 Cov.: 30 AF XY: 0.00000275 AC XY: 2 AN XY: 727004

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: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Phenylketonuria Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Dec 05, 2023	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Counsyl	Oct 09, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 07, 2024	This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 320 of the PAH protein (p.Lys320Asn). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with PAH-related conditions (PMID: 8659548, 11678552, 12655553, 12655554, 23764561, 24350308; Invitae). ClinVar contains an entry for this variant (Variation ID: 102910). 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 not expected to disrupt PAH protein function with a negative predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University Hospital Muenster	Mar 31, 2022	ACMG categories: PS5,PM3,PM7,PP1,PP3,PP5 -

not provided Pathogenic:1 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Oct 03, 2016	The K320N variant has previously been reported in association with mild PKU and hyperphenylalaninemia and is classified as a BH4 responsive variant (Lücke et al., 2003; Steinfeld et al., 2004; Blau et al., 2004). -
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	0.70
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;D
Eigen	Benign	0.12
Eigen_PC	Benign	-0.0073
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Pathogenic	0.91	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Uncertain	-4.3	D;D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.012	D;D
Sift4G	Uncertain	0.011	D;D
Polyphen		1.0	D;.
Vest4		0.91
MutPred		0.86		Loss of methylation at K320 (P = 0.025);.;
MVP		0.99
MPC		0.25
ClinPred		0.99	D
GERP RS		1.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.89
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs199475615; hg19: chr12-103240682;