NM_000277.3:c.71A>T

Variant names:

• chr12-102912888-T-A
• rs539994406
• NM_000277.3:c.71A>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP2

The NM_000277.3(PAH):​c.71A>T​(p.Tyr24Phe) variant causes a missense change. The variant allele was found at a frequency of 0.000000687 in 1,455,498 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y24C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.10
• Publications: 1 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• 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.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000277.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAH	NM_000277.3	MANE Select	c.71A>T	p.Tyr24Phe	missense	Exon 2 of 13	NP_000268.1
	PAH	NM_001354304.2		c.71A>T	p.Tyr24Phe	missense	Exon 3 of 14	NP_001341233.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAH	ENST00000553106.6	TSL:1 MANE Select	c.71A>T	p.Tyr24Phe	missense	Exon 2 of 13	ENSP00000448059.1
	PAH	ENST00000549111.5	TSL:1	n.167A>T		non_coding_transcript_exon	Exon 2 of 6
	PAH	ENST00000307000.7	TSL:5	c.56A>T	p.Tyr19Phe	missense	Exon 3 of 14	ENSP00000303500.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251378 AF XY: 0.00000736

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: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455498 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 724606

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33364

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26080

East Asian (EAS) AF: 0.00 AC: 0 AN: 39612

South Asian (SAS) AF: 0.00 AC: 0 AN: 86144

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53384

Middle Eastern (MID) AF: 0.000174 AC: 1 AN: 5746

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1106266

Other (OTH) AF: 0.00 AC: 0 AN: 60182

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000425 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Uncertain	25
DANN	Benign	0.97
DEOGEN2	Uncertain	0.62	D
Eigen	Uncertain	0.28
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Uncertain	0.88	D
M_CAP	Pathogenic	0.56	D
MetaRNN	Uncertain	0.47	T
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Benign	0.55	N
PhyloP100		5.1
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-2.1	N
REVEL	Pathogenic	0.67
Sift	Benign	0.11	T
Sift4G	Benign	0.47	T
Polyphen		0.99	D
Vest4		0.68
MutPred		0.37		Loss of sheet (P = 0.0457)
MVP		0.98
MPC		0.22
ClinPred		0.56	D
GERP RS		5.4
Varity_R		0.46
gMVP		0.48
Mutation Taster		=62/38	polymorphism

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

Other links and lift over

dbSNP: rs539994406; hg19: chr12-103306666;