NM_014363.6:c.7504C>T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_014363.6(SACS):c.7504C>T(p.Arg2502*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000103 in 1,461,782 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

SACS
NM_014363.6 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:11O:1

Conservation

PhyloP100: 4.43

Variant links:

Genes affected

SACS (HGNC:10519): (sacsin molecular chaperone) This gene encodes the sacsin protein, which includes a UbL domain at the N-terminus, a DnaJ domain, and a HEPN domain at the C-terminus. The gene is highly expressed in the central nervous system, also found in skin, skeletal muscles and at low levels in the pancreas. This gene includes a very large exon spanning more than 12.8 kb. Mutations in this gene result in autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS), a neurodegenerative disorder characterized by early-onset cerebellar ataxia with spasticity and peripheral neuropathy. The authors of a publication on the effects of siRNA-mediated sacsin knockdown concluded that sacsin protects against mutant ataxin-1 and suggest that "the large multi-domain sacsin protein is able to recruit Hsp70 chaperone action and has the potential to regulate the effects of other ataxia proteins" (Parfitt et al., PubMed: 19208651). A pseudogene associated with this gene is located on chromosome 11. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

SACS links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 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 66 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 13-23336372-G-A is Pathogenic according to our data. Variant chr13-23336372-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 5513.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23336372-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SACS	NM_014363.6 link	c.7504C>T	p.Arg2502*	stop_gained	Exon 10 of 10	ENST00000382292.9	NP_055178.3	Q9NZJ4-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SACS	ENST00000382292.9 link	c.7504C>T	p.Arg2502*	stop_gained	Exon 10 of 10	5	NM_014363.6	ENSP00000371729.3		Q9NZJ4-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251338

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135832

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1461782

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727188

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000126

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000111

Hom.:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:11Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Charlevoix-Saguenay spastic ataxia

Pathogenic:8Other:1

Sep 05, 2021

Genome-Nilou Lab

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 10, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 01, 2020

Medical Genetics Laboratory, Tarbiat Modares University

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 01, 2000

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Oct 25, 2017

Molecular Genetics Laboratory, BC Children's and BC Women's Hospitals

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Jan 01, 2022

PROSPAX: an integrated multimodal progression chart in spastic ataxias, Center for Neurology; Hertie-Institute for Clinical Brain Research

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

- -

Sep 03, 2015

Counsyl

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 14, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: SACS c.7504C>T (p.Arg2502X) results in a premature termination codon, predicted to cause a truncation of the encoded protein, which is a commonly known mechanism for disease. While this variant is not expected to result in nonsense mediated decay, it is predicted to disrupt the last 2,078 amino acids of the protein. Variants downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 2e-05 in 251338 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.7504C>T has been reported in the literature in multiple individuals affected with Autosomal Recessive Spastic Ataxia Of Charlevoix-Saguenay (e.g., Engert_2000). These data indicate that the variant is very likely to be associated with disease. The following publication was ascertained in the context of this evaluation (PMID: 10655055). Seven submitters have reported clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Spastic paraplegia

Pathogenic:1

Nov 06, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg2502*) in the SACS gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 2078 amino acid(s) of the SACS protein. This variant is present in population databases (rs281865118, gnomAD 0.006%). This premature translational stop signal has been observed in individuals with autosomal recessive spastic ataxia of Charlevoix-Saguenay (PMID: 10655055, 30901567). This variant is also known as g.5254C>T. ClinVar contains an entry for this variant (Variation ID: 5513). For these reasons, this variant has been classified as Pathogenic. -

Hereditary spastic paraplegia

Pathogenic:1

Dec 12, 2016

Genome Diagnostics Laboratory, The Hospital for Sick Children

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Pathogenic:1

Oct 23, 2020

Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.51

BayesDel_noAF

Pathogenic

0.50

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Uncertain

0.62

Eigen_PC

Uncertain

0.47

FATHMM_MKL

Uncertain

0.89

Vest4

0.97

GERP RS

2.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.6

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over