rs747784107
Variant summary
Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong
The NM_033453.4(ITPA):c.520G>A(p.Ala174Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000223 in 1,613,756 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A174V) has been classified as Uncertain significance.
Frequency
Consequence
NM_033453.4 missense
Scores
Clinical Significance
Conservation
Publications
- genetic developmental and epileptic encephalopathyInheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
- developmental and epileptic encephalopathy, 35Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
- inosine triphosphatase deficiencyInheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -2 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| ITPA | NM_033453.4 | c.520G>A | p.Ala174Thr | missense_variant | Exon 8 of 8 | ENST00000380113.8 | NP_258412.1 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152194Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000199 AC: 5AN: 250730 AF XY: 0.0000221 show subpopulations
GnomAD4 exome AF: 0.0000226 AC: 33AN: 1461562Hom.: 0 Cov.: 31 AF XY: 0.0000289 AC XY: 21AN XY: 727072 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152194Hom.: 0 Cov.: 33 AF XY: 0.0000269 AC XY: 2AN XY: 74354 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Inosine triphosphatase deficiency Uncertain:1
This sequence change replaces alanine with threonine at codon 174 of the ITPA protein (p.Ala174Thr). The alanine residue is weakly conserved and there is a small physicochemical difference between alanine and threonine. This variant is present in population databases (rs747784107, ExAC 0.01%). This variant has not been reported in the literature in individuals affected with ITPA-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The threonine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at