chr3-4683555-G-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_001378452.1(ITPR1):​c.3327+4G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,406 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 predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

ITPR1
NM_001378452.1 splice_region, intron

Scores

2
Splicing: ADA: 0.00002082
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.204

Publications

0 publications found
Variant links:
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: Ambry Genetics, G2P, Genomics England PanelApp, PanelApp Australia, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
  • spinocerebellar ataxia type 29
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet
  • spinocerebellar ataxia type 15/16
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.84).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ITPR1NM_001378452.1 linkc.3327+4G>T splice_region_variant, intron_variant Intron 27 of 61 ENST00000649015.2 NP_001365381.1
ITPR1NM_001168272.2 linkc.3282+4G>T splice_region_variant, intron_variant Intron 26 of 60 NP_001161744.1 Q14643-2
ITPR1NM_001099952.4 linkc.3300+4G>T splice_region_variant, intron_variant Intron 27 of 58 NP_001093422.2 Q14643-3B4DER3Q59H91
ITPR1NM_002222.7 linkc.3255+4G>T splice_region_variant, intron_variant Intron 26 of 57 NP_002213.5 Q14643-4B4DER3B4DGH1Q59H91

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ITPR1ENST00000649015.2 linkc.3327+4G>T splice_region_variant, intron_variant Intron 27 of 61 NM_001378452.1 ENSP00000497605.1 Q14643-1
ITPR1ENST00000354582.12 linkc.3300+4G>T splice_region_variant, intron_variant Intron 27 of 61 5 ENSP00000346595.8 A0A3F2YNW8
ITPR1ENST00000648266.1 linkc.3300+4G>T splice_region_variant, intron_variant Intron 27 of 61 ENSP00000498014.1 A0A3B3IU04
ITPR1ENST00000650294.1 linkc.3282+4G>T splice_region_variant, intron_variant Intron 26 of 60 ENSP00000498056.1 A0A3B3ITU8
ITPR1ENST00000443694.5 linkc.3282+4G>T splice_region_variant, intron_variant Intron 26 of 60 1 ENSP00000401671.2 Q14643-2
ITPR1ENST00000648309.1 linkc.3255+4G>T splice_region_variant, intron_variant Intron 24 of 58 ENSP00000497026.1 Q14643-5
ITPR1ENST00000357086.10 linkc.3300+4G>T splice_region_variant, intron_variant Intron 27 of 58 1 ENSP00000349597.4 Q14643-3
ITPR1ENST00000456211.8 linkc.3255+4G>T splice_region_variant, intron_variant Intron 26 of 57 1 ENSP00000397885.2 Q14643-4
ITPR1ENST00000648038.1 linkc.1137+4G>T splice_region_variant, intron_variant Intron 8 of 41 ENSP00000497872.1 A0A3B3ITQ1
ITPR1ENST00000648431.1 linkc.627+4G>T splice_region_variant, intron_variant Intron 5 of 38 ENSP00000498149.1 A0A3B3IU05
ITPR1ENST00000648212.1 linkc.234+4G>T splice_region_variant, intron_variant Intron 3 of 38 ENSP00000498022.1 A0A3B3IU13

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461406
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
726912
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111606
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60366
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Uncertain:1
Nov 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 26 of the ITPR1 gene. It does not directly change the encoded amino acid sequence of the ITPR1 protein. It affects a nucleotide within the consensus splice site. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ITPR1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1966498). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.84
CADD
Benign
16
DANN
Benign
0.29
PhyloP100
-0.20

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000021
dbscSNV1_RF
Benign
0.0040
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs2306878; hg19: chr3-4725239; API