3-4788144-G-A

Variant names:

• chr3-4788144-G-A
• rs878853174
• NM_001378452.1:c.6808+5G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001378452.1(ITPR1):​c.6808+5G>A variant causes a splice region, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000694 in 1,441,308 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: ITPR1 NM_001378452.1 splice_region, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.30
• Publications: 0 publications found

Genes affected

ITPR1 (HGNC:6180): (inositol 1,4,5-trisphosphate receptor type 1) This gene encodes an intracellular receptor for inositol 1,4,5-trisphosphate. Upon stimulation by inositol 1,4,5-trisphosphate, this receptor mediates calcium release from the endoplasmic reticulum. Mutations in this gene cause spinocerebellar ataxia type 15, a disease associated with an heterogeneous group of cerebellar disorders. Multiple transcript variants have been identified for this gene. [provided by RefSeq, Nov 2009]

ITPR1 Gene-Disease associations (from GenCC):

• aniridia-cerebellar ataxia-intellectual disability syndrome

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
• spinocerebellar ataxia type 29

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, G2P, Labcorp Genetics (formerly Invitae)
• spinocerebellar ataxia type 15/16

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)

ENSG00000235978 (HGNC:):

ACMG classification

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

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001378452.1. 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
	ITPR1	NM_001378452.1	MANE Select	c.6808+5G>A		splice_region intron	N/A	NP_001365381.1	Q14643-1
	ITPR1	NM_001168272.2		c.6763+5G>A		splice_region intron	N/A	NP_001161744.1	Q14643-2
	ITPR1	NM_001099952.4		c.6664+5G>A		splice_region intron	N/A	NP_001093422.2	Q14643-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ITPR1	ENST00000649015.2	MANE Select	c.6808+5G>A		splice_region intron	N/A	ENSP00000497605.1	Q14643-1
	ITPR1	ENST00000354582.12	TSL:5	c.6784+5G>A		splice_region intron	N/A	ENSP00000346595.8	A0A3F2YNW8
	ITPR1	ENST00000648266.1		c.6781+5G>A		splice_region intron	N/A	ENSP00000498014.1	A0A3B3IU04

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.94e-7 AC: 1 AN: 1441308 Hom.: 0 Cov.: 30 AF XY: 0.00000140 AC XY: 1 AN XY: 714754

African (AFR) AF: 0.00 AC: 0 AN: 33118

American (AMR) AF: 0.00 AC: 0 AN: 41682

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25702

East Asian (EAS) AF: 0.00 AC: 0 AN: 39074

South Asian (SAS) AF: 0.00 AC: 0 AN: 82654

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52500

Middle Eastern (MID) AF: 0.000174 AC: 1 AN: 5740

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1101064

Other (OTH) AF: 0.00 AC: 0 AN: 59774

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.48
CADD	Benign	15
DANN	Benign	0.96
PhyloP100		7.3

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.83		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.83		Position offset: -5

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

Other links and lift over

dbSNP: rs878853174; hg19: chr3-4829828;