NM_000277.3:c.1278T>C

Variant names:

• chr12-102840437-A-G
• rs59326968
• NM_000277.3:c.1278T>C

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4 BA1

This summary comes from the ClinGen Evidence Repository: PAH-specific ACMG/AMP criteria applied: BA1: MAF=0.16641; BP4: no impact on gene in SIFT, Polyphen2, MutationTaster. In summary this variant meets criteria to be classified as benign for phenylketonuria in an autosomal recessive manner based on the ACMG/AMP criteria applied as specified by the PAH Expert Panel: (BA1, BP4). LINK:https://erepo.genome.network/evrepo/ui/classification/CA145978/MONDO:0009861/006

• Frequency:
  • Genomes: 𝑓 0.041 (467 hom., cov: 32)
  • Exomes 𝑓: 0.0044 (389 hom.)
• Consequence: PAH NM_000277.3 synonymous
• Clinical Significance: Benign reviewed by expert panel B:10 O:1
• Conservation: PhyloP100: 0.0610

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 Benign. Variant got -9 ACMG points.

• BP4: For more information check the summary or visit ClinGen Evidence Repository.
• BA1: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PAH	NM_000277.3	c.1278T>C	p.Asn426Asn	synonymous_variant	Exon 12 of 13	ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.1278T>C	p.Asn426Asn	synonymous_variant	Exon 13 of 14		NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.1278T>C	p.Asn426Asn	synonymous_variant	Exon 12 of 13	1	NM_000277.3	ENSP00000448059.1

Frequencies

GnomAD3 genomes AF: 0.0406 AC: 6175 AN: 152134 Hom.: 461 Cov.: 32

Gnomad AFR AF: 0.141

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0143

Gnomad ASJ AF: 0.000288

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00949

Gnomad NFE AF: 0.000764

Gnomad OTH AF: 0.0244

GnomAD3 exomes AF: 0.0110 AC: 2772 AN: 251446 Hom.: 192 AF XY: 0.00780 AC XY: 1060 AN XY: 135898

Gnomad AFR exome AF: 0.148

Gnomad AMR exome AF: 0.00752

Gnomad ASJ exome AF: 0.000397

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.000392

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.000501

Gnomad OTH exome AF: 0.00635

GnomAD4 exome AF: 0.00444 AC: 6484 AN: 1461546 Hom.: 389 Cov.: 31 AF XY: 0.00384 AC XY: 2791 AN XY: 727098

Gnomad4 AFR exome AF: 0.148

Gnomad4 AMR exome AF: 0.00883

Gnomad4 ASJ exome AF: 0.000536

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.000394

Gnomad4 FIN exome AF: 0.0000562

Gnomad4 NFE exome AF: 0.000427

Gnomad4 OTH exome AF: 0.00921

GnomAD4 genome AF: 0.0408 AC: 6205 AN: 152252 Hom.: 467 Cov.: 32 AF XY: 0.0391 AC XY: 2908 AN XY: 74432

Gnomad4 AFR AF: 0.142

Gnomad4 AMR AF: 0.0143

Gnomad4 ASJ AF: 0.000288

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000415

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000765

Gnomad4 OTH AF: 0.0241

Alfa AF: 0.0233 Hom.: 125

Bravo AF: 0.0470

Asia WGS AF: 0.0120 AC: 42 AN: 3478

EpiCase AF: 0.000436

EpiControl AF: 0.00101

ClinVar

Significance: Benign

Submissions summary: Benign:10 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

not provided Benign:4 Other:1

Jan 13, 2021

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 01, 2019

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

Breakthrough Genomics, Breakthrough Genomics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

-

DeBelle Laboratory for Biochemical Genetics, MUHC/MCH RESEARCH INSTITUTE

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Jul 31, 2017

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The PAH c.1278T>C (p.Asn426Asn) variant involves the alteration of a non-conserved nucleotide causing a synonymous change and 5/5 splice prediction tools predict no significant impact on normal splicing. ESE finder predicts that this variant may alter ESE binding. However, these predictions have yet to be confirmed by functional studies. This variant was found in 1666/121610 control chromosomes (104 homozygotes), predominantly in the African cohort at a frequency of 0.14655 (1525/10406). This frequency is about 19 times the estimated maximal expected allele frequency of a pathogenic PAH variant (0.0079057), suggesting this is likely a benign polymorphism found primarily in population(s) of African origin. A publication, Acosta_2001, classifies the variant as a polymorphism, along with multiple clinical diagnostic laboratories classify the variant as "likely benign/benign." Taken together, this variant is classified as benign. -

Phenylketonuria Benign:4

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Aug 10, 2018

ClinGen PAH Variant Curation Expert Panel

Significance: Benign

Review Status: reviewed by expert panel

Collection Method: curation

PAH-specific ACMG/AMP criteria applied: BA1: MAF=0.16641; BP4: no impact on gene in SIFT, Polyphen2, MutationTaster. In summary this variant meets criteria to be classified as benign for phenylketonuria in an autosomal recessive manner based on the ACMG/AMP criteria applied as specified by the PAH Expert Panel: (BA1, BP4). -

Sep 16, 2020

Natera, Inc.

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

not specified Benign:2

-

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 18, 2012

Eurofins Ntd Llc (ga)

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	2.0
DANN	Benign	0.59
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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

LitVar

Other links and lift over

dbSNP: rs59326968; hg19: chr12-103234215;