rs202199411

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_014363.6(SACS):​c.9508C>T​(p.Arg3170*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000822 in 1,460,418 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 Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. R3170R) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

SACS
NM_014363.6 stop_gained

Scores

2
4
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 2.18

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • Charlevoix-Saguenay spastic ataxia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Myriad Women’s Health

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 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 268 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 13-23334368-G-A is Pathogenic according to our data. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23334368-G-A is described in CliVar as Pathogenic/Likely_pathogenic. Clinvar id is 280094.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SACSNM_014363.6 linkc.9508C>T p.Arg3170* 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.9508C>T p.Arg3170* stop_gained Exon 10 of 10 5 NM_014363.6 ENSP00000371729.3 Q9NZJ4-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000399
AC:
1
AN:
250380
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000822
AC:
12
AN:
1460418
Hom.:
0
Cov.:
37
AF XY:
0.00000964
AC XY:
7
AN XY:
726400
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33396
American (AMR)
AF:
0.00
AC:
0
AN:
44608
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26102
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39672
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86020
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53212
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5720
European-Non Finnish (NFE)
AF:
0.0000108
AC:
12
AN:
1111354
Other (OTH)
AF:
0.00
AC:
0
AN:
60334
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.496
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.0000618
Hom.:
0
Bravo
AF:
0.0000227
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charlevoix-Saguenay spastic ataxia Pathogenic:5
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

- -

Dec 24, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SACS c.9508C>T (p.Arg3170X) results in a premature termination codon and is predicted to cause a truncation of the encoded protein, which is a commonly known mechanism for disease. Although this premature termination is not expected to result in nonsense mediated decay, truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 4e-06 in 250380 control chromosomes (gnomAD). c.9508C>T has been reported in the literature in at least one compound heterozygous individual affected with Autosomal Recessive Spastic Ataxia Of Charlevoix-Saguenay (Thiffault_2013). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five ClinVar submitters have assessed the variant since 2014: two classified the variant as likely pathogenic, and three as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Sep 05, 2021
Genome-Nilou Lab
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 05, 2016
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Mar 27, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:2
Sep 27, 2024
Athena Diagnostics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The frequency of this variant in the general population is consistent with pathogenicity. (http://gnomad.broadinstitute.org) This variant is not expected to cause loss of protein expression through nonsense-mediated decay. However, it disrupts a critical region of the protein, and therefore, is expected to severely disrupt its function. This variant has been identified in at least one individual with clinical features associated with this gene. -

Oct 22, 2024
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Nonsense variant predicted to result in protein truncation, as the last 1410 amino acids are lost, and other loss-of-function variants have been reported downstream in HGMD; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 31980526, 23250129) -

Spastic paraplegia Pathogenic:1
Aug 29, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is present in population databases (rs202199411, gnomAD 0.002%). For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the SACS protein in which other variant(s) (p.Arg3903*) have been determined to be pathogenic (PMID: 19892370, 21745802). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. ClinVar contains an entry for this variant (Variation ID: 280094). This premature translational stop signal has been observed in individual(s) with autosomal recessive spastic ataxia of Charlevoix-Saguenay (PMID: 23250129). This sequence change creates a premature translational stop signal (p.Arg3170*) in the SACS gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 1410 amino acid(s) of the SACS protein. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.49
CADD
Pathogenic
38
DANN
Uncertain
1.0
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.43
FATHMM_MKL
Uncertain
0.87
D
PhyloP100
2.2
Vest4
0.97
GERP RS
4.0
Mutation Taster
=0/200
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs202199411; hg19: chr13-23908507; COSMIC: COSV66533660; API