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GeneBe

20-3209609-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_033453.4(ITPA):c.58C>A(p.Leu20Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000254 in 1,613,858 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

ITPA
NM_033453.4 missense

Scores

3
11
5

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.32
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
ITPANM_033453.4 linkuse as main transcriptc.58C>A p.Leu20Met missense_variant 1/8 ENST00000380113.8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
ITPAENST00000380113.8 linkuse as main transcriptc.58C>A p.Leu20Met missense_variant 1/81 NM_033453.4 P1Q9BY32-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152130
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
250726
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135598
show subpopulations
Gnomad AFR exome
AF:
0.0000617
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000353
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000274
AC:
40
AN:
1461728
Hom.:
0
Cov.:
31
AF XY:
0.0000289
AC XY:
21
AN XY:
727158
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000342
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152130
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74316
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000625
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsNov 09, 2021The c.58C>A (p.L20M) alteration is located in exon 1 (coding exon 1) of the ITPA gene. This alteration results from a C to A substitution at nucleotide position 58, causing the leucine (L) at amino acid position 20 to be replaced by a methionine (M). 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
Benign
0.24
BayesDel_addAF
Benign
-0.0079
T
BayesDel_noAF
Uncertain
-0.070
Cadd
Uncertain
25
Dann
Uncertain
1.0
DEOGEN2
Uncertain
0.76
D;.
Eigen
Pathogenic
0.74
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Pathogenic
0.98
D;T
M_CAP
Benign
0.073
D
MetaRNN
Uncertain
0.58
D;D
MetaSVM
Uncertain
0.28
D
MutationAssessor
Pathogenic
4.0
H;H
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.72
T
PROVEAN
Benign
-1.9
N;N
REVEL
Uncertain
0.47
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0030
D;D
Polyphen
1.0
D;.
Vest4
0.47
MutPred
0.70
Loss of methylation at K19 (P = 0.0367);Loss of methylation at K19 (P = 0.0367);
MVP
0.66
MPC
0.97
ClinPred
0.99
D
GERP RS
4.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.94
gMVP
0.41

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs758704128; hg19: chr20-3190255; API