13-23330971-G-T

Variant names:

• chr13-23330971-G-T
• rs778808568
• NM_014363.6:c.12905C>A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_014363.6(SACS):​c.12905C>A​(p.Ser4302Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000821 in 1,461,844 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S4302C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: SACS NM_014363.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 8.14
• Publications: 0 publications found

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: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, PanelApp Australia, G2P, Myriad Women’s Health, Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.25602144).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_014363.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SACS	NM_014363.6	MANE Select	c.12905C>A	p.Ser4302Tyr	missense	Exon 10 of 10	NP_055178.3
	SACS	NM_001437336.1		c.12932C>A	p.Ser4311Tyr	missense	Exon 11 of 11	NP_001424265.1	A0A804HIQ1
	SACS	NM_001278055.2		c.12464C>A	p.Ser4155Tyr	missense	Exon 8 of 8	NP_001264984.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SACS	ENST00000382292.9	TSL:5 MANE Select	c.12905C>A	p.Ser4302Tyr	missense	Exon 10 of 10	ENSP00000371729.3	Q9NZJ4-1
	SACS	ENST00000455470.6	TSL:1	c.2432-1487C>A		intron	N/A	ENSP00000406565.2	H0Y6M8
	SACS	ENST00000682944.1		c.12932C>A	p.Ser4311Tyr	missense	Exon 11 of 11	ENSP00000507173.1	A0A804HIQ1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00 AC: 0 AN: 250918 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000821 AC: 12 AN: 1461844 Hom.: 0 Cov.: 33 AF XY: 0.00000963 AC XY: 7 AN XY: 727222

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53410

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000899 AC: 10 AN: 1111974

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.0000113

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Charlevoix-Saguenay spastic ataxia (1)
-	1	-	not specified (1)
-	1	-	Spastic paraplegia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Uncertain	0.052	T
BayesDel_noAF	Benign	-0.16
CADD	Uncertain	24
DANN	Benign	0.97
DEOGEN2	Benign	0.31	T
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.95	D
M_CAP	Benign	0.076	D
MetaRNN	Benign	0.26	T
MetaSVM	Uncertain	0.11	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		8.1
PrimateAI	Uncertain	0.51	T
PROVEAN	Benign	-1.4	N
REVEL	Uncertain	0.41
Sift	Uncertain	0.010	D
Sift4G	Uncertain	0.028	D
Polyphen		0.30	B
Vest4		0.31
MVP		0.89
ClinPred		0.92	D
GERP RS		5.0
Varity_R		0.18
gMVP		0.46
Mutation Taster		=46/54	disease causing

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

Other links and lift over

dbSNP: rs778808568; hg19: chr13-23905110; COSMIC: COSV66539221;