rs1554792421

Variant names:

• chr9-136429751-CTT-C
• rs1554792421
• NM_019892.6:c.1857_1858delAA

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_019892.6(INPP5E):​c.1857_1858delAA​(p.Arg620ThrfsTer77) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. K619K) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: INPP5E NM_019892.6 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.81
• Publications: 0 publications found

Genes affected

INPP5E (HGNC:21474): (inositol polyphosphate-5-phosphatase E) The protein encoded by this gene is an inositol 1,4,5-trisphosphate (InsP3) 5-phosphatase. InsP3 5-phosphatases hydrolyze Ins(1,4,5)P3, which mobilizes intracellular calcium and acts as a second messenger mediating cell responses to various stimulation. Studies of the mouse counterpart suggest that this protein may hydrolyze phosphatidylinositol 3,4,5-trisphosphate and phosphatidylinositol 3,5-bisphosphate on the cytoplasmic Golgi membrane and thereby regulate Golgi-vesicular trafficking. Mutations in this gene cause Joubert syndrome; a clinically and genetically heterogenous group of disorders characterized by midbrain-hindbrain malformation and various associated ciliopathies that include retinal dystrophy, nephronophthisis, liver fibrosis and polydactyly. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

INPP5E Gene-Disease associations (from GenCC):

• Joubert syndrome 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), G2P
• MORM syndrome

  Inheritance: AR Classification: DEFINITIVE, MODERATE, SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, G2P, Genomics England PanelApp, ClinGen, Orphanet
• COACH syndrome 1

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Joubert syndrome with ocular defect

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 8 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
INPP5E	NM_019892.6	c.1857_1858delAA	p.Arg620ThrfsTer77	frameshift_variant	Exon 10 of 10	ENST00000371712.4	NP_063945.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
INPP5E	ENST00000371712.4	c.1857_1858delAA	p.Arg620ThrfsTer77	frameshift_variant	Exon 10 of 10	1	NM_019892.6	ENSP00000360777.3
INPP5E	ENST00000676019.1	c.1755_1756delAA	p.Arg586ThrfsTer77	frameshift_variant	Exon 10 of 10			ENSP00000501984.1

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

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Feb 29, 2016

Genetic Services Laboratory, University of Chicago

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		1.8

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1554792421; hg19: chr9-139324203;