rs761089024

Variant summary

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

The NM_014363.6(SACS):​c.5629C>T​(p.Arg1877*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,884 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 (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

SACS
NM_014363.6 stop_gained

Scores

2
2
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6U:1

Conservation

PhyloP100: 1.25
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 89 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 13-23338247-G-A is Pathogenic according to our data. Variant chr13-23338247-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 371545.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr13-23338247-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SACSNM_014363.6 linkc.5629C>T p.Arg1877* 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.5629C>T p.Arg1877* stop_gained Exon 10 of 10 5 NM_014363.6 ENSP00000371729.3 Q9NZJ4-1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152078
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000798
AC:
2
AN:
250656
Hom.:
0
AF XY:
0.00000738
AC XY:
1
AN XY:
135426
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:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461806
Hom.:
0
Cov.:
36
AF XY:
0.00000275
AC XY:
2
AN XY:
727204
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152078
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74262
show subpopulations
Gnomad4 AFR
AF:
0.0000242
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000166
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6Uncertain:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charlevoix-Saguenay spastic ataxia Pathogenic:5
Jun 12, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 12, 2016
Counsyl
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 29, 2022
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

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

- -

Jan 01, 2022
PROSPAX: an integrated multimodal progression chart in spastic ataxias, Center for Neurology; Hertie-Institute for Clinical Brain Research
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

Spastic paraplegia Pathogenic:1
Nov 04, 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.Arg1877*) in the SACS gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 2703 amino acid(s) of the SACS protein. This variant is present in population databases (rs761089024, gnomAD 0.005%). This premature translational stop signal has been observed in individual(s) with clinical features of spastic ataxia (PMID: 20852969). ClinVar contains an entry for this variant (Variation ID: 371545). This variant disrupts a region of the SACS protein in which other variant(s) (p.Tyr4538*) have been determined to be pathogenic (Invitae). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Hereditary spastic paraplegia Uncertain:1
Mar 07, 2017
Unit for Genetic & Epidemiological Research on Neurological Disorders, Instituto de Investigação e Inovação em Saúde
Significance: Uncertain significance
Review Status: flagged submission
Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.51
D
BayesDel_noAF
Pathogenic
0.33
CADD
Pathogenic
36
DANN
Uncertain
1.0
Eigen
Uncertain
0.31
Eigen_PC
Benign
0.12
FATHMM_MKL
Benign
0.74
D
Vest4
0.94
GERP RS
1.5

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: rs761089024; hg19: chr13-23912386; COSMIC: COSV66533403; API