NM_000277.3:c.1218A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PP4PM3PM5PM2

This summary comes from the ClinGen Evidence Repository: The c.1218A>G (p.Ile406Met) variant in PAH is reported in 2 individuals with non-PKU HPA. BH4 assessment was not stated. It was detected with a known pathogenic variant, p.Arg408Trp. (PMID:23357515) This variant has a low allele frequency in gnomAD and ExAC (MAF=0.00003) and is absent in 1000G. Computational evidence is discordant. Another missense change at this amino acid is interpreted as likely pathogenic by the PAH VCEP (p.I406T). In summary, this variant meets criteria to be classified as likely pathogenic for PAH. PAH-specific ACMG/AMP criteria applied: PM2, PM3, PM5, PP4. LINK:https://erepo.genome.network/evrepo/ui/classification/CA6748708/MONDO:0009861/006

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

PAH
NM_000277.3 missense

Scores

8
3
8

Clinical Significance

Likely pathogenic reviewed by expert panel P:4U:2

Conservation

PhyloP100: -0.0300

Publications

3 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: Likely_pathogenic. The variant received 7 ACMG points.

PM2
For more information check the summary or visit ClinGen Evidence Repository.
PM3
For more information check the summary or visit ClinGen Evidence Repository.
PM5
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 rank MANE Protein UniProt
PAHNM_000277.3 linkc.1218A>G p.Ile406Met missense_variant Exon 12 of 13 ENST00000553106.6 NP_000268.1 P00439A0A024RBG4
PAHNM_001354304.2 linkc.1218A>G p.Ile406Met missense_variant Exon 13 of 14 NP_001341233.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PAHENST00000553106.6 linkc.1218A>G p.Ile406Met missense_variant Exon 12 of 13 1 NM_000277.3 ENSP00000448059.1 P00439

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
151936
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251432
AF XY:
0.0000221
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461492
Hom.:
0
Cov.:
31
AF XY:
0.0000124
AC XY:
9
AN XY:
727072
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53408
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.00000720
AC:
8
AN:
1111684
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60380
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
151936
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74180
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41338
American (AMR)
AF:
0.00
AC:
0
AN:
15244
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4796
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68010
Other (OTH)
AF:
0.00
AC:
0
AN:
2080
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
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:
0.0000203
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:4Uncertain:2
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Phenylketonuria Pathogenic:4Uncertain:1
Jul 01, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 406 of the PAH protein (p.Ile406Met). This variant is present in population databases (rs773526027, gnomAD 0.002%). This missense change has been observed in individual(s) with PAH-related conditions (PMID: 23357515, 32668217). ClinVar contains an entry for this variant (Variation ID: 552907). 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%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on PAH function (PMID: 31208052). This variant disrupts the p.Ile406 amino acid residue in PAH. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 10234516, 32668217). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Dec 09, 2018
ClinGen PAH Variant Curation Expert Panel
Significance:Likely pathogenic
Review Status:reviewed by expert panel
Collection Method:curation

The c.1218A>G (p.Ile406Met) variant in PAH is reported in 2 individuals with non-PKU HPA. BH4 assessment was not stated. It was detected with a known pathogenic variant, p.Arg408Trp. (PMID: 23357515) This variant has a low allele frequency in gnomAD and ExAC (MAF=0.00003) and is absent in 1000G. Computational evidence is discordant. Another missense change at this amino acid is interpreted as likely pathogenic by the PAH VCEP (p.I406T). In summary, this variant meets criteria to be classified as likely pathogenic for PAH. PAH-specific ACMG/AMP criteria applied: PM2, PM3, PM5, PP4. -

Jul 17, 2017
Counsyl
Significance:Uncertain significance
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. -

May 18, 2021
Pars Genome Lab
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 22, 2021
Genome-Nilou Lab
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Oct 12, 2018
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.38
CADD
Benign
21
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.86
D;D
Eigen
Benign
-0.074
Eigen_PC
Benign
-0.15
FATHMM_MKL
Benign
0.65
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.84
D
MetaRNN
Pathogenic
0.96
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Benign
1.4
L;.
PhyloP100
-0.030
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
-2.2
N;N
REVEL
Pathogenic
0.78
Sift
Benign
0.085
T;T
Sift4G
Benign
0.22
T;T
Polyphen
0.97
D;.
Vest4
0.84
MutPred
0.81
Gain of methylation at R408 (P = 0.0643);.;
MVP
0.94
MPC
0.23
ClinPred
0.50
T
GERP RS
-1.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.69
gMVP
0.86
Mutation Taster
=1/99
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
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

Other links and lift over

dbSNP: rs773526027; hg19: chr12-103234275; API