chr13-23337095-G-T

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_StrongBP6BS2

The NM_014363.6(SACS):​c.6781C>A​(p.Leu2261Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00531 in 1,613,958 control chromosomes in the GnomAD database, including 28 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0047 ( 5 hom., cov: 33)
Exomes 𝑓: 0.0054 ( 23 hom. )

Consequence

SACS
NM_014363.6 missense

Scores

3
8
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:10

Conservation

PhyloP100: 7.76
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]

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -9 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.010582924).
BP6
Variant 13-23337095-G-T is Benign according to our data. Variant chr13-23337095-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 240901.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Benign=5, Uncertain_significance=1}. Variant chr13-23337095-G-T is described in Lovd as [Likely_pathogenic]. Variant chr13-23337095-G-T is described in Lovd as [Likely_benign]. Variant chr13-23337095-G-T is described in Lovd as [Benign].
BS2
High Homozygotes in GnomAd4 at 5 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
SACSNM_014363.6 linkuse as main transcriptc.6781C>A p.Leu2261Ile missense_variant 10/10 ENST00000382292.9 NP_055178.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
SACSENST00000382292.9 linkuse as main transcriptc.6781C>A p.Leu2261Ile missense_variant 10/105 NM_014363.6 ENSP00000371729 P1Q9NZJ4-1

Frequencies

GnomAD3 genomes
AF:
0.00475
AC:
722
AN:
152130
Hom.:
5
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00109
Gnomad AMI
AF:
0.0197
Gnomad AMR
AF:
0.000458
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0258
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00543
Gnomad OTH
AF:
0.00478
GnomAD3 exomes
AF:
0.00477
AC:
1198
AN:
250910
Hom.:
7
AF XY:
0.00474
AC XY:
643
AN XY:
135696
show subpopulations
Gnomad AFR exome
AF:
0.000744
Gnomad AMR exome
AF:
0.000231
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0210
Gnomad NFE exome
AF:
0.00622
Gnomad OTH exome
AF:
0.00295
GnomAD4 exome
AF:
0.00536
AC:
7841
AN:
1461710
Hom.:
23
Cov.:
37
AF XY:
0.00504
AC XY:
3667
AN XY:
727156
show subpopulations
Gnomad4 AFR exome
AF:
0.000836
Gnomad4 AMR exome
AF:
0.000291
Gnomad4 ASJ exome
AF:
0.0000766
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0201
Gnomad4 NFE exome
AF:
0.00586
Gnomad4 OTH exome
AF:
0.00343
GnomAD4 genome
AF:
0.00474
AC:
722
AN:
152248
Hom.:
5
Cov.:
33
AF XY:
0.00576
AC XY:
429
AN XY:
74440
show subpopulations
Gnomad4 AFR
AF:
0.00108
Gnomad4 AMR
AF:
0.000457
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.0258
Gnomad4 NFE
AF:
0.00543
Gnomad4 OTH
AF:
0.00473
Alfa
AF:
0.00470
Hom.:
3
Bravo
AF:
0.00296
TwinsUK
AF:
0.00566
AC:
21
ALSPAC
AF:
0.00545
AC:
21
ESP6500AA
AF:
0.000681
AC:
3
ESP6500EA
AF:
0.00524
AC:
45
ExAC
AF:
0.00482
AC:
585
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00398
EpiControl
AF:
0.00593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:10
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Charlevoix-Saguenay spastic ataxia Uncertain:2Benign:4
Benign, criteria provided, single submitterclinical testingGenome-Nilou LabSep 05, 2021- -
Likely benign, no assertion criteria providedclinical testingNatera, Inc.Jan 04, 2020- -
Benign, criteria provided, single submitterclinical testingClinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical CenterMay 31, 2017- -
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This 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. -
Likely benign, criteria provided, single submitterclinical testingGenome Diagnostics Laboratory, University Medical Center UtrechtOct 09, 2014- -
Uncertain significance, no assertion criteria providedclinical testingDepartment of Pathology and Laboratory Medicine, Sinai Health System-The p.Leu266Ile variant was identified in the proband in trans with the SACS p.Thr458Ile variant of uncertain significance. The p.Leu2261Ile variant was previously identified in the literature, in compound heterozygous state with the p.Ser527* variant in a male patient with juvenile onset motor neuropathy, ataxia, and spasticity; these variants were considered causative (Bansagi_2017_PMID:28251916). The p.Leu2261Ile variant was also identified in compound heterozygous form (with p.Ser527*) in two affected siblings with disease onset in their 40s; the variants were reported as confirmed pathogenic. Both siblings were affected by gait disturbance and cerebellar ataxia. In addition, one sibling (male) was positive for demyelinating sensorimotor neuropathy, and MRI indicated generalized atrophy. The other sibling (female) was observed to have jerky ocular pursuit and optic atrophy (Pyle_2015_PMID:25497598). The variant was identified in dbSNP (rs146722795) and ClinVar (Conflicting interpretations of pathogenicity. Uncertain significance [1], benign [2], likely benign [2]. Classified as Uncertain significance for ARSACS in 2016 by Ilumina, likely benign in 2014 by Genome Diagnostics Centre and University Medical Centre Utrecht for ARSACS, Benign for spastic paraplegia in 2017 by Erasmus Medical Centre, Benign in 2017 by Invitae, and Likely benign in 2017 by Athena Diagnostics) databases. The variant was identified in control databases in 1397 of 282308 chromosomes (8 homozygous) at a frequency of 0.004948 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: European (Finnish) in 542 of 25098 chromosomes (freq: 0.0216), European (non-Finnish) in 792 of 128852 chromosomes (freq: 0.006147), Other in 27 of 7194 chromosomes (freq: 0.003753), African in 26 of 24834 chromosomes (freq: 0.001047), Latino in 10 of 35420 chromosomes (freq: 0.000282), but was not observed in the Ashkenazi Jewish, East Asian, and South Asian populations. The p.Leu266 residue is conserved in mammals and other organisms; computational analyses (MUT Assessor, SIFT, Polyphen 2, MT, FATHMM, DANN, MetaLR, Revel) predict a deleterious impact to the protein. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -
not provided Benign:3
Likely benign, criteria provided, single submitterclinical testingGeneDxMay 21, 2020This variant is associated with the following publications: (PMID: 23280630, 19779133, 24457356, 28251916, 25497598) -
Benign, criteria provided, single submitterclinical testingAthena DiagnosticsDec 26, 2018- -
Benign, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenAug 01, 2024SACS: BS1, BS2 -
Spastic paraplegia Benign:1
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 31, 2024- -
SACS-related disorder Benign:1
Likely benign, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJul 08, 2019This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -
Hereditary spastic paraplegia Benign:1
Likely benign, criteria provided, single submitterclinical testingGenome Diagnostics Laboratory, The Hospital for Sick ChildrenFeb 01, 2019- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.083
T
BayesDel_noAF
Uncertain
0.12
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.27
.;T
Eigen
Uncertain
0.58
Eigen_PC
Uncertain
0.65
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.98
D;D
MetaRNN
Benign
0.011
T;T
MetaSVM
Uncertain
0.38
D
MutationAssessor
Uncertain
2.1
.;M
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.69
T
PROVEAN
Benign
-0.88
N;N
REVEL
Pathogenic
0.79
Sift
Benign
0.17
T;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
0.82
.;P
Vest4
0.67
MVP
0.85
ClinPred
0.019
T
GERP RS
5.8
Varity_R
0.16
gMVP
0.43

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: rs146722795; hg19: chr13-23911234; COSMIC: COSV104428963; API