chr3-4645604-A-C

Position:

• chr3-4645604-A-C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_001378452.1(ITPR1):​c.731A>C​(p.His244Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H244R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: ITPR1 NM_001378452.1 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.22

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-4645604-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 427186.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), ITPR1. . Gene score misZ 5.5951 (greater than the threshold 3.09). Trascript score misZ 6.2026 (greater than threshold 3.09). GenCC has associacion of gene with spinocerebellar ataxia type 15/16, aniridia-cerebellar ataxia-intellectual disability syndrome, spinocerebellar ataxia type 29.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.976
• PP5: Variant 3-4645604-A-C is Pathogenic according to our data. Variant chr3-4645604-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 522002.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ITPR1	NM_001378452.1	c.731A>C	p.His244Pro	missense_variant	10/62	ENST00000649015.2
ITPR1	NM_001168272.2	c.731A>C	p.His244Pro	missense_variant	10/61
ITPR1	NM_001099952.4	c.731A>C	p.His244Pro	missense_variant	10/59
ITPR1	NM_002222.7	c.731A>C	p.His244Pro	missense_variant	10/58

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ITPR1	ENST00000649015.2	c.731A>C	p.His244Pro	missense_variant	10/62		NM_001378452.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 23, 2024

The c.731A>C (p.H244P) alteration is located in exon 10 (coding exon 8) of the ITPR1 gene. This alteration results from an A to C substitution at nucleotide position 731, causing the histidine (H) at amino acid position 244 to be replaced by a proline (P)._x000D_ _x000D_ for ITPR1-related congenital non-progressive spinocerebellar ataxia (SCA29); however, its clinical significance for Gillespie syndrome is uncertain and it is unlikely to be causative of ITPR1-related spinocerebellar ataxia (SCA15). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.95	.;.;.;.;.;.;.;.;D;.;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;.
M_CAP	Pathogenic	0.74	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M;M;.;.;M;.;.;.;M;M;M
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-9.3	D;D;.;D;D;.;D;.;.;.;D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D;D;.;D;D;.;D;.;.;.;D
Sift4G	Pathogenic	0.0	D;D;.;.;D;.;D;.;.;.;D
Polyphen		0.99, 1.0	.;.;.;.;.;.;D;.;D;.;.
Vest4		0.97
MutPred		0.85		Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);Loss of sheet (P = 0.0457);
MVP		0.99
MPC		2.2
ClinPred		1.0	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.96
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
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

LitVar

Other links and lift over

dbSNP: rs1085308010; hg19: chr3-4687288;