8-81671011-G-GAGCCC

Position:

• chr8-81671011-G-GAGCCC

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_005536.4(IMPA1):​c.493_494insGGGCT​(p.Ser165TrpfsTer10) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: IMPA1 NM_005536.4 frameshift
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 3.63

Genes affected

IMPA1 (HGNC:6050): (inositol monophosphatase 1) This gene encodes an enzyme that dephosphorylates myo-inositol monophosphate to generate free myo-inositol, a precursor of phosphatidylinositol, and is therefore an important modulator of intracellular signal transduction via the production of the second messengers myoinositol 1,4,5-trisphosphate and diacylglycerol. This enzyme can also use myo-inositol-1,3-diphosphate, myo-inositol-1,4-diphosphate, scyllo-inositol-phosphate, glucose-1-phosphate, glucose-6-phosphate, fructose-1-phosphate, beta-glycerophosphate, and 2'-AMP as substrates. This enzyme shows magnesium-dependent phosphatase activity and is inhibited by therapeutic concentrations of lithium. Inhibition of inositol monophosphate hydroylosis and subsequent depletion of inositol for phosphatidylinositol synthesis may explain the anti-manic and anti-depressive effects of lithium administered to treat bipolar disorder. Alternative splicing results in multiple transcript variants encoding distinct isoforms. A pseudogene of this gene is also present on chromosome 8q21.13. [provided by RefSeq, Dec 2014]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-81671011-G-GAGCCC is Pathogenic according to our data. Variant chr8-81671011-G-GAGCCC is described in ClinVar as [Pathogenic]. Clinvar id is 375412.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IMPA1	NM_005536.4	c.493_494insGGGCT	p.Ser165TrpfsTer10	frameshift_variant	7/9	ENST00000256108.10	NP_005527.1
IMPA1	NM_001144878.2	c.670_671insGGGCT	p.Ser224TrpfsTer10	frameshift_variant	8/10		NP_001138350.1
IMPA1	NM_001144879.2	c.457+2829_457+2830insGGGCT		intron_variant			NP_001138351.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IMPA1	ENST00000256108.10	c.493_494insGGGCT	p.Ser165TrpfsTer10	frameshift_variant	7/9	1	NM_005536.4	ENSP00000256108	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Intellectual disability, autosomal recessive 59 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Apr 07, 2022

- -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1057519491; hg19: chr8-82583246;