rs34982958

Variant summary

Our verdict is Benign. The variant received -18 ACMG points: 2P and 20B. PM1BP4_StrongBP6_Very_StrongBS1BS2

The NM_033453.4(ITPA):​c.278A>G​(p.Glu93Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00105 in 1,613,920 control chromosomes in the GnomAD database, including 17 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E93Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0058 ( 7 hom., cov: 32)
Exomes 𝑓: 0.00056 ( 10 hom. )

Consequence

ITPA
NM_033453.4 missense

Scores

3
4
10

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 5.77

Publications

3 publications found
Variant links:
Genes affected
ITPA (HGNC:6176): (inosine triphosphatase) This gene encodes an inosine triphosphate pyrophosphohydrolase. The encoded protein hydrolyzes inosine triphosphate and deoxyinosine triphosphate to the monophosphate nucleotide and diphosphate. This protein, which is a member of the HAM1 NTPase protein family, is found in the cytoplasm and acts as a homodimer. Defects in the encoded protein can result in inosine triphosphate pyrophosphorylase deficiency which causes an accumulation of ITP in red blood cells. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jun 2012]
ITPA Gene-Disease associations (from GenCC):
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • developmental and epileptic encephalopathy, 35
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
  • inosine triphosphatase deficiency
    Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -18 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_033453.4
BP4
Computational evidence support a benign effect (MetaRNN=0.008969754).
BP6
Variant 20-3215295-A-G is Benign according to our data. Variant chr20-3215295-A-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 445902.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00579 (881/152242) while in subpopulation AFR AF = 0.0202 (838/41538). AF 95% confidence interval is 0.019. There are 7 homozygotes in GnomAd4. There are 401 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 7 AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033453.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ITPA
NM_033453.4
MANE Select
c.278A>Gp.Glu93Gly
missense
Exon 5 of 8NP_258412.1
ITPA
NM_001424408.1
c.278A>Gp.Glu93Gly
missense
Exon 5 of 9NP_001411337.1
ITPA
NM_001424409.1
c.404A>Gp.Glu135Gly
missense
Exon 6 of 9NP_001411338.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
ITPA
ENST00000380113.8
TSL:1 MANE Select
c.278A>Gp.Glu93Gly
missense
Exon 5 of 8ENSP00000369456.3
ITPA
ENST00000455664.6
TSL:1
c.227A>Gp.Glu76Gly
missense
Exon 5 of 8ENSP00000413282.1
ITPA
ENST00000399838.3
TSL:1
c.155A>Gp.Glu52Gly
missense
Exon 3 of 6ENSP00000382732.3

Frequencies

GnomAD3 genomes
AF:
0.00579
AC:
881
AN:
152124
Hom.:
7
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0202
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00190
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:
0.0000294
Gnomad OTH
AF:
0.00575
GnomAD2 exomes
AF:
0.00146
AC:
366
AN:
251454
AF XY:
0.000979
show subpopulations
Gnomad AFR exome
AF:
0.0201
Gnomad AMR exome
AF:
0.000896
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:
0.000814
GnomAD4 exome
AF:
0.000560
AC:
819
AN:
1461678
Hom.:
10
Cov.:
30
AF XY:
0.000506
AC XY:
368
AN XY:
727160
show subpopulations
African (AFR)
AF:
0.0202
AC:
676
AN:
33470
American (AMR)
AF:
0.00130
AC:
58
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000162
AC:
18
AN:
1111834
Other (OTH)
AF:
0.00106
AC:
64
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
39
78
116
155
194
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
24
48
72
96
120
<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:
0.00579
AC:
881
AN:
152242
Hom.:
7
Cov.:
32
AF XY:
0.00539
AC XY:
401
AN XY:
74424
show subpopulations
African (AFR)
AF:
0.0202
AC:
838
AN:
41538
American (AMR)
AF:
0.00190
AC:
29
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68024
Other (OTH)
AF:
0.00569
AC:
12
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
51
102
153
204
255
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.00237
Hom.:
7
Bravo
AF:
0.00655
ESP6500AA
AF:
0.0179
AC:
79
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.00186
AC:
226
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

ClinVar submissions as Germline

Significance:Benign/Likely benign
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
2
not provided (2)
-
-
1
Inosine triphosphatase deficiency (1)
-
-
1
Inosine triphosphatase deficiency;C4225256:Developmental and epileptic encephalopathy, 35 (1)
-
-
1
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Benign
-0.40
T
BayesDel_noAF
Benign
-0.33
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.80
D
Eigen
Benign
-0.043
Eigen_PC
Benign
0.12
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
D
MetaRNN
Benign
0.0090
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.68
N
PhyloP100
5.8
PrimateAI
Uncertain
0.58
T
PROVEAN
Pathogenic
-5.0
D
REVEL
Benign
0.11
Sift
Uncertain
0.029
D
Sift4G
Benign
0.11
T
Polyphen
0.0010
B
Vest4
0.29
MVP
0.48
MPC
0.34
ClinPred
0.035
T
GERP RS
4.7
Varity_R
0.46
gMVP
0.57
Mutation Taster
=87/13
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

Publications

Other links and lift over

dbSNP: rs34982958; hg19: chr20-3195941; API