4-56400825-G-T

Position:

• chr4-56400825-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_002703.5(PPAT):​c.973C>A​(p.Pro325Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PPAT NM_002703.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.60

Genes affected

PPAT (HGNC:9238): (phosphoribosyl pyrophosphate amidotransferase) The protein encoded by this gene is a member of the purine/pyrimidine phosphoribosyltransferase family. It is a regulatory allosteric enzyme that catalyzes the first step of de novo purine nucleotide biosythetic pathway. This gene and PAICS/AIRC gene, a bifunctional enzyme catalyzing steps six and seven of this pathway, are located in close proximity on chromosome 4, and divergently transcribed from an intergenic region. [provided by RefSeq, Mar 2011]

PPAT (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.961

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PPAT	NM_002703.5	c.973C>A	p.Pro325Thr	missense_variant	8/11	ENST00000264220.6	NP_002694.3
PPAT	NR_156493.2	n.1028C>A		non_coding_transcript_exon_variant	8/11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PPAT	ENST00000264220.6	c.973C>A	p.Pro325Thr	missense_variant	8/11	1	NM_002703.5	ENSP00000264220.2
PPAT	ENST00000425339.2	n.92C>A		non_coding_transcript_exon_variant	1/3	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 19, 2024

The c.973C>A (p.P325T) alteration is located in exon 8 (coding exon 8) of the PPAT gene. This alteration results from a C to A substitution at nucleotide position 973, causing the proline (P) at amino acid position 325 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.78	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.75	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	4.7	H
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-7.7	D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		0.99	D
Vest4		0.97
MutPred		0.73		Gain of glycosylation at P325 (P = 0.0322);
MVP		0.93
MPC		2.2
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.72
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-57266991;