13-23365280-A-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_014363.6(SACS):​c.346-3T>A variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,558,106 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

SACS
NM_014363.6 splice_region, splice_polypyrimidine_tract, intron

Scores

2
Splicing: ADA: 0.5747
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 1.06
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 Likely_benign. Variant got -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.73).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
SACSNM_014363.6 linkuse as main transcriptc.346-3T>A splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant ENST00000382292.9 NP_055178.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SACSENST00000382292.9 linkuse as main transcriptc.346-3T>A splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant 5 NM_014363.6 ENSP00000371729 P1Q9NZJ4-1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152180
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.000864
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:
0.0000462
AC:
10
AN:
216630
Hom.:
0
AF XY:
0.0000601
AC XY:
7
AN XY:
116558
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000200
Gnomad ASJ exome
AF:
0.000317
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000106
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000142
AC:
20
AN:
1405808
Hom.:
0
Cov.:
24
AF XY:
0.0000157
AC XY:
11
AN XY:
699660
show subpopulations
Gnomad4 AFR exome
AF:
0.0000311
Gnomad4 AMR exome
AF:
0.000145
Gnomad4 ASJ exome
AF:
0.000156
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000748
Gnomad4 OTH exome
AF:
0.0000171
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152298
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74472
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.000864
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:
0.0000868
Hom.:
0
Bravo
AF:
0.0000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Spastic paraplegia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpApr 16, 2022This sequence change falls in intron 5 of the SACS gene. It does not directly change the encoded amino acid sequence of the SACS protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs186506382, gnomAD 0.04%). This variant has not been reported in the literature in individuals affected with SACS-related conditions. ClinVar contains an entry for this variant (Variation ID: 411688). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Charlevoix-Saguenay spastic ataxia Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Nov 11, 2019- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.73
CADD
Benign
15
DANN
Benign
0.69

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.57
dbscSNV1_RF
Benign
0.39
SpliceAI score (max)
0.070
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: rs186506382; hg19: chr13-23939419; API