rs774682589

Variant names:

• chr13-23341277-A-G
• rs774682589
• NM_014363.6:c.2599T>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_014363.6(SACS):​c.2599T>C​(p.Tyr867His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,356 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. Y867Y) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: SACS NM_014363.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 8.95
• 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), G2P, Myriad Women’s Health, Laboratory for Molecular Medicine, Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.835

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.2599T>C	p.Tyr867His	missense	Exon 10 of 10	NP_055178.3
	SACS	NM_001437336.1		c.2626T>C	p.Tyr876His	missense	Exon 11 of 11	NP_001424265.1
	SACS	NM_001278055.2		c.2158T>C	p.Tyr720His	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.2599T>C	p.Tyr867His	missense	Exon 10 of 10	ENSP00000371729.3
	SACS	ENST00000455470.6	TSL:1	c.2431+168T>C		intron	N/A	ENSP00000406565.2
	SACS	ENST00000682944.1		c.2626T>C	p.Tyr876His	missense	Exon 11 of 11	ENSP00000507173.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461356 Hom.: 0 Cov.: 35 AF XY: 0.00000550 AC XY: 4 AN XY: 726942

African (AFR) AF: 0.00 AC: 0 AN: 33460

American (AMR) AF: 0.00 AC: 0 AN: 44680

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39682

South Asian (SAS) AF: 0.00 AC: 0 AN: 86140

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53394

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

European-Non Finnish (NFE) AF: 0.00000810 AC: 9 AN: 1111728

Other (OTH) AF: 0.0000166 AC: 1 AN: 60378

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	Charlevoix-Saguenay spastic ataxia (2)
-	1	-	not provided (1)
-	1	-	Spastic paraplegia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.26
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.92	D
M_CAP	Pathogenic	0.30	D
MetaRNN	Pathogenic	0.84	D
MetaSVM	Pathogenic	0.89	D
MutationAssessor	Benign	2.0	M
PhyloP100		8.9
PrimateAI	Uncertain	0.69	T
PROVEAN	Uncertain	-3.5	D
REVEL	Pathogenic	0.80
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.96	D
Vest4		0.85
MutPred		0.59		Gain of catalytic residue at L863 (P = 0)
MVP		0.93
ClinPred		0.96	D
GERP RS		6.0
Varity_R		0.69
gMVP		0.77
Mutation Taster		=26/74	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: rs774682589; hg19: chr13-23915416;