20-3213196-CCA-AGC

Variant names:

• chr20-3213196-CCA-AGC
• NM_033453.4:c.94_96delCCAinsAGC
• ITPA p.Pro32Ser

Variant summary

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

The NM_033453.4(ITPA):​c.94_96delCCAinsAGC​(p.Pro32Ser) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P32T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ITPA NM_033453.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.18
• Publications: 0 publications found

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

ACMG classification

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

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITPA	NM_033453.4	MANE Select	c.94_96delCCAinsAGC	p.Pro32Ser	missense	N/A	NP_258412.1	A0A0S2Z3W7
	ITPA	NM_001424408.1		c.94_96delCCAinsAGC	p.Pro32Ser	missense	N/A	NP_001411337.1
	ITPA	NM_001424409.1		c.220_222delCCAinsAGC	p.Pro74Ser	missense	N/A	NP_001411338.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITPA	ENST00000380113.8	TSL:1 MANE Select	c.94_96delCCAinsAGC	p.Pro32Ser	missense	N/A	ENSP00000369456.3	Q9BY32-1
	ITPA	ENST00000455664.6	TSL:1	c.43_45delCCAinsAGC	p.Pro15Ser	missense	N/A	ENSP00000413282.1	Q9BY32-2
	ITPA	ENST00000399838.3	TSL:1	c.67-789_67-787delCCAinsAGC		intron	N/A	ENSP00000382732.3	Q9BY32-3

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		6.2

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr20-3193842;