rs774647600

Positions:

chr13-23330402-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_014363.6(SACS):c.13474G>A(p.Val4492Met) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,874 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. V4492V) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

SACS
NM_014363.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.17

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.41900095).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SACS	NM_014363.6 linkuse as main transcript	c.13474G>A	p.Val4492Met	missense_variant	10/10	ENST00000382292.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SACS	ENST00000382292.9 linkuse as main transcript	c.13474G>A	p.Val4492Met	missense_variant	10/10	5	NM_014363.6	P1	Q9NZJ4-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251392

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135862

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461874

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000480

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Spastic paraplegia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 26, 2021

This sequence change replaces valine with methionine at codon 4492 of the SACS protein (p.Val4492Met). The valine residue is moderately conserved and there is a small physicochemical difference between valine and methionine. This variant is present in population databases (rs774647600, ExAC 0.001%). This variant has not been reported in the literature in individuals affected with SACS-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Pathogenic

0.19

BayesDel_noAF

Uncertain

0.040

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.37

.;T

Eigen

Uncertain

0.64

Eigen_PC

Pathogenic

0.66

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.91

D;D

M_CAP

Uncertain

0.10

MetaRNN

Benign

0.42

T;T

MetaSVM

Uncertain

0.36

MutationAssessor

Benign

0.69

.;N

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Uncertain

0.78

PROVEAN

Benign

-0.35

N;N

REVEL

Uncertain

0.52

Sift

Benign

0.042

D;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

.;D

Vest4

0.39

MutPred

0.41

.;Gain of catalytic residue at D4489 (P = 0.0184);

MVP

0.82

ClinPred

0.74

GERP RS

5.8

Varity_R

0.43

gMVP

0.63

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over