rs773751064

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1BP4BS1_Supporting

The NM_000270.4(PNP):​c.815A>G​(p.Glu272Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000384 in 1,614,058 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000040 ( 0 hom. )

Consequence

PNP
NM_000270.4 missense

Scores

5
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 8.12

Publications

0 publications found
Variant links:
Genes affected
PNP (HGNC:7892): (purine nucleoside phosphorylase) This gene encodes an enzyme which reversibly catalyzes the phosphorolysis of purine nucleosides. The enzyme is trimeric, containing three identical subunits. Mutations which result in nucleoside phosphorylase deficiency result in defective T-cell (cell-mediated) immunity but can also affect B-cell immunity and antibody responses. Neurologic disorders may also be apparent in patients with immune defects. A known polymorphism at aa position 51 that does not affect enzyme activity has been described. A pseudogene has been identified on chromosome 2. [provided by RefSeq, Jul 2008]
PNP Gene-Disease associations (from GenCC):
  • purine nucleoside phosphorylase deficiency
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM1
In a chain Purine nucleoside phosphorylase (size 288) in uniprot entity PNPH_HUMAN there are 12 pathogenic changes around while only 3 benign (80%) in NM_000270.4
BP4
Computational evidence support a benign effect (MetaRNN=0.29431248).
BS1
Variant frequency is greater than expected in population sas. GnomAdExome4 allele frequency = 0.0000397 (58/1461890) while in subpopulation SAS AF = 0.000475 (41/86258). AF 95% confidence interval is 0.00036. There are 0 homozygotes in GnomAdExome4. There are 39 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PNPNM_000270.4 linkc.815A>G p.Glu272Gly missense_variant Exon 6 of 6 ENST00000361505.10 NP_000261.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PNPENST00000361505.10 linkc.815A>G p.Glu272Gly missense_variant Exon 6 of 6 1 NM_000270.4 ENSP00000354532.6

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152168
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000676
AC:
17
AN:
251468
AF XY:
0.000110
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:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000397
AC:
58
AN:
1461890
Hom.:
0
Cov.:
31
AF XY:
0.0000536
AC XY:
39
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
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:
39700
South Asian (SAS)
AF:
0.000475
AC:
41
AN:
86258
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:
0.0000117
AC:
13
AN:
1112010
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
4
8
11
15
19
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:
0.0000263
AC:
4
AN:
152168
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74332
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41442
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
TwinsUK
AF:
0.000270
AC:
1
ExAC
AF:
0.0000824
AC:
10
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Oct 04, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.815A>G (p.E272G) alteration is located in exon 6 (coding exon 6) of the PNP gene. This alteration results from a A to G substitution at nucleotide position 815, causing the glutamic acid (E) at amino acid position 272 to be replaced by a glycine (G). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Purine-nucleoside phosphorylase deficiency Uncertain:1
Feb 20, 2018
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamic acid with glycine at codon 272 of the PNP protein (p.Glu272Gly). The glutamic acid residue is weakly conserved and there is a moderate physicochemical difference between glutamic acid and glycine. This variant is present in population databases (rs773751064, ExAC 0.05%). This variant has not been reported in the literature in individuals with PNP-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.22
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.090
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.53
D
Eigen
Benign
-0.081
Eigen_PC
Benign
0.035
LIST_S2
Benign
0.58
T
M_CAP
Uncertain
0.14
D
MetaRNN
Benign
0.29
T
MetaSVM
Uncertain
-0.27
T
MutationAssessor
Benign
1.6
L
PhyloP100
8.1
PrimateAI
Benign
0.37
T
PROVEAN
Uncertain
-3.5
D
Sift
Benign
0.20
T
Sift4G
Benign
0.16
T
Vest4
0.48
ClinPred
0.29
T
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.68
gMVP
0.65
Mutation Taster
=43/57
disease causing

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: rs773751064; hg19: chr14-20944705; API