rs281865118

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

2
4
1

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]

Genome browser will be placed here

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
SACSNM_014363.6 linkc.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
SACSENST00000382292.9 linkc.7504C>T p.Arg2502* stop_gained Exon 10 of 10 5 NM_014363.6 ENSP00000371729.3 Q9NZJ4-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251338
Hom.:
0
AF XY:
0.0000221
AC XY:
3
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:
15
AN:
1461782
Hom.:
0
Cov.:
37
AF XY:
0.00000963
AC XY:
7
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.:
33
Alfa
AF:
0.0000111
Hom.:
0
ExAC
AF:
0.00000824
AC:
1

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
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.47
FATHMM_MKL
Uncertain
0.89
D
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.

Other links and lift over

dbSNP: rs281865118; hg19: chr13-23910511; API