rs578227905

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_033453.4(ITPA):​c.388C>T​(p.Arg130Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,350 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

ITPA
NM_033453.4 missense

Scores

4
15

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.22
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 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.35311446).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ITPANM_033453.4 linkc.388C>T p.Arg130Cys missense_variant Exon 6 of 8 ENST00000380113.8 NP_258412.1 Q9BY32-1A0A0S2Z3W7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ITPAENST00000380113.8 linkc.388C>T p.Arg130Cys missense_variant Exon 6 of 8 1 NM_033453.4 ENSP00000369456.3 Q9BY32-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000400
AC:
1
AN:
249730
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135376
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000164
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461016
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
726878
show subpopulations
Gnomad4 AFR exome
AF:
0.00
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:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000656
AC:
1
AN:
152334
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74492
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000653
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
ExAC
AF:
0.00000824
AC:
1

ClinVar

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

Submissions by phenotype

Inosine triphosphatase deficiency Uncertain:1
Dec 27, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine with cysteine at codon 130 of the ITPA protein (p.Arg130Cys). The arginine residue is weakly conserved and there is a large physicochemical difference between arginine and cysteine. This variant is present in population databases (rs578227905, ExAC 0.009%). This variant has not been reported in the literature in individuals with ITPA-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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
0.097
BayesDel_addAF
Benign
-0.10
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
21
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.58
D;.;.
Eigen
Uncertain
0.23
Eigen_PC
Benign
0.12
FATHMM_MKL
Benign
0.15
N
LIST_S2
Uncertain
0.89
D;D;D
M_CAP
Benign
0.0065
T
MetaRNN
Benign
0.35
T;T;T
MetaSVM
Benign
-0.50
T
MutationAssessor
Benign
1.8
L;.;.
PrimateAI
Benign
0.29
T
PROVEAN
Benign
-0.72
N;N;N
REVEL
Benign
0.18
Sift
Benign
0.15
T;T;T
Sift4G
Benign
0.070
T;T;T
Polyphen
1.0
D;.;.
Vest4
0.53
MutPred
0.61
Loss of MoRF binding (P = 0.0093);.;.;
MVP
0.55
MPC
0.92
ClinPred
0.48
T
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.18
gMVP
0.60

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: rs578227905; hg19: chr20-3199255; API