13-23339119-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_014363.6(SACS):​c.4757A>G​(p.Asn1586Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000172 in 1,610,990 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00017 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00017 ( 0 hom. )

Consequence

SACS
NM_014363.6 missense

Scores

1
8
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 7.67

Publications

2 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: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_014363.6

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SACSNM_014363.6 linkc.4757A>G p.Asn1586Ser missense_variant 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.4757A>G p.Asn1586Ser missense_variant Exon 10 of 10 5 NM_014363.6 ENSP00000371729.3 Q9NZJ4-1

Frequencies

GnomAD3 genomes
AF:
0.000171
AC:
26
AN:
152214
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.000294
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000157
AC:
39
AN:
248938
AF XY:
0.000186
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000583
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000275
Gnomad OTH exome
AF:
0.000663
GnomAD4 exome
AF:
0.000172
AC:
251
AN:
1458776
Hom.:
0
Cov.:
36
AF XY:
0.000167
AC XY:
121
AN XY:
725278
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33394
American (AMR)
AF:
0.000112
AC:
5
AN:
44500
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26004
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39658
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85794
European-Finnish (FIN)
AF:
0.0000376
AC:
2
AN:
53258
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5758
European-Non Finnish (NFE)
AF:
0.000211
AC:
234
AN:
1110130
Other (OTH)
AF:
0.0000995
AC:
6
AN:
60280
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
15
30
46
61
76
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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
AF:
0.000171
AC:
26
AN:
152214
Hom.:
0
Cov.:
33
AF XY:
0.000188
AC XY:
14
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41454
American (AMR)
AF:
0.000131
AC:
2
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000294
AC:
20
AN:
68040
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000220
Hom.:
0
Bravo
AF:
0.000170
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.000157
AC:
19
EpiCase
AF:
0.000654
EpiControl
AF:
0.000297

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Charlevoix-Saguenay spastic ataxia Uncertain:3
Sep 16, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

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

- -

Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided Uncertain:2
Jun 17, 2020
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 15, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

not specified Uncertain:1
Dec 24, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SACS c.4757A>G (p.Asn1586Ser) results in a conservative amino acid change in the encoded protein sequence. Three of four in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00016 in 248938 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in SACS causing Charlevoix-Saguenay spastic ataxia, allowing no conclusion about variant significance. To our knowledge, no occurrence of c.4757A>G in individuals affected with Charlevoix-Saguenay spastic ataxia and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 527996). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Hereditary spastic paraplegia Uncertain:1
Dec 12, 2016
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Spastic paraplegia Benign:1
Mar 14, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.19
T
BayesDel_noAF
Benign
-0.20
CADD
Benign
21
DANN
Uncertain
1.0
DEOGEN2
Benign
0.19
.;T
Eigen
Benign
0.15
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.95
D;D
M_CAP
Benign
0.049
D
MetaRNN
Uncertain
0.48
T;T
MetaSVM
Uncertain
-0.024
T
MutationAssessor
Benign
0.69
.;N
PhyloP100
7.7
PrimateAI
Uncertain
0.73
T
PROVEAN
Benign
-0.62
N;N
REVEL
Uncertain
0.36
Sift
Benign
0.46
T;T
Sift4G
Pathogenic
0.0
D;D
Polyphen
0.29
.;B
Vest4
0.86
MVP
0.87
ClinPred
0.069
T
GERP RS
6.0
Varity_R
0.10
gMVP
0.45
Mutation Taster
=73/27
polymorphism

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: rs201558584; hg19: chr13-23913258; API