12-102852881-G-A

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_000277.3(PAH):​c.776C>T​(p.Ala259Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,982 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A259T) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

PAH
NM_000277.3 missense

Scores

17
1
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5O:1

Conservation

PhyloP100: 10.0

Publications

12 publications found
Variant links:
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 Gene-Disease associations (from GenCC):
  • phenylketonuria
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Myriad Women’s Health
  • classic phenylketonuria
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • maternal phenylketonuria
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • mild hyperphenylalaninemia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • mild phenylketonuria
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 20 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 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 chr12-102852882-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 102831.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 440 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Gene score misZ: -0.64755 (below the threshold of 3.09). Trascript score misZ: -0.0084567 (below the threshold of 3.09). GenCC associations: The gene is linked to phenylketonuria, tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria, maternal phenylketonuria, classic phenylketonuria, mild phenylketonuria, mild hyperphenylalaninemia.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.945
PP5
Variant 12-102852881-G-A is Pathogenic according to our data. Variant chr12-102852881-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 602.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PAHNM_000277.3 linkc.776C>T p.Ala259Val missense_variant Exon 7 of 13 ENST00000553106.6 NP_000268.1 P00439A0A024RBG4
PAHNM_001354304.2 linkc.776C>T p.Ala259Val missense_variant Exon 8 of 14 NP_001341233.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PAHENST00000553106.6 linkc.776C>T p.Ala259Val missense_variant Exon 7 of 13 1 NM_000277.3 ENSP00000448059.1 P00439
PAHENST00000307000.7 linkc.761C>T p.Ala254Val missense_variant Exon 8 of 14 5 ENSP00000303500.2 J3KND8
PAHENST00000549247.6 linkn.535C>T non_coding_transcript_exon_variant Exon 1 of 6 2
PAHENST00000635477.1 linkc.-65C>T upstream_gene_variant 5 ENSP00000489230.1 A0A0U1RQY4

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152142
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251340
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.00000137
AC:
2
AN:
1461840
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1111976
Other (OTH)
AF:
0.00
AC:
0
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74328
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41418
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000137
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Phenylketonuria Pathogenic:5
Jan 10, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 20, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 259 of the PAH protein (p.Ala259Val). This variant is present in population databases (rs118203921, gnomAD 0.007%). This missense change has been observed in individual(s) with phenylketonuria (PMID: 2035532, 18299955, 26666653). ClinVar contains an entry for this variant (Variation ID: 602). 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 with a positive predictive value of 80%. Experimental studies have shown that this missense change affects PAH function (PMID: 8304187, 9799096, 10479481). For these reasons, this variant has been classified as Pathogenic. -

Aug 23, 2016
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jul 31, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PAH c.776C>T (p.Ala259Val) results in a non-conservative amino acid change located in the aromatic amino acid hydroxylase, C-terminal domain (IPR019774) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251340 control chromosomes (gnomAD). c.776C>T has been reported in the literature in multiple individuals affected with Phenylalanine Hydroxylase Deficiency (Phenylketonuria) (e.g. Koch_1997, Benit_1999, Jeannesson-Thivisol_2015). 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 and found the variant results in <5% of normal activity (e.g. Benit_1999). The following publications have been ascertained in the context of this evaluation (PMID: 10479481, 26666653, 9169088). Two submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic and likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Jun 01, 1991
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

not provided Other:1
-
DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
30
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
1.0
D;D
Eigen
Pathogenic
1.2
Eigen_PC
Pathogenic
1.1
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.60
D
MetaRNN
Pathogenic
0.95
D;D
MetaSVM
Pathogenic
0.92
D
MutationAssessor
Pathogenic
4.5
H;.
PhyloP100
10
PrimateAI
Pathogenic
0.85
D
PROVEAN
Uncertain
-3.8
D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0010
D;D
Polyphen
1.0
D;.
Vest4
0.91
MVP
0.99
MPC
0.23
ClinPred
1.0
D
GERP RS
5.7
PromoterAI
-0.034
Neutral
Varity_R
0.98
gMVP
0.97
Mutation Taster
=1/99
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs118203921; hg19: chr12-103246659; API