rs864622268

Variant names:

• chr2-32137129-CAG-C
• rs864622268
• NM_014946.4:c.1437_1438delAG

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_014946.4(SPAST):​c.1437_1438delAG​(p.Arg479SerfsTer8) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SPAST NM_014946.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 6.96
• Publications: 1 publications found

Genes affected

SPAST (HGNC:11233): (spastin) This gene encodes a member of the AAA (ATPases associated with a variety of cellular activities) protein family. Members of this protein family share an ATPase domain and have roles in diverse cellular processes including membrane trafficking, intracellular motility, organelle biogenesis, protein folding, and proteolysis. The use of alternative translational initiation sites in this gene results in a single transcript variant that can produce isoforms that differ in the length of their N-terminus and which thereby differ in the efficiency of their export from the nucleus to the cytoplasm. In addition, alternative splicing results in multiple transcript variants that encode isoforms that differ in other protein regions as well. One isoform of this gene has been shown to be a microtubule-severing enzyme that regulates microtubule abundance, mobility, and plus-end distribution. Mutations in this gene cause the most frequent form of autosomal dominant spastic paraplegia 4. [provided by RefSeq, May 2018]

SPAST Gene-Disease associations (from GenCC):

• hereditary spastic paraplegia 4

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet, Genomics England PanelApp, Illumina, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Charlevoix-Saguenay spastic ataxia

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• neurodevelopmental disorder

  Inheritance: AD Classification: STRONG Submitted by: G2P
• SPAST-related motor disorder

  Inheritance: AR Classification: STRONG Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-32137129-CAG-C is Pathogenic according to our data. Variant chr2-32137129-CAG-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 219826.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_014946.4. 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
	SPAST	NM_014946.4	MANE Select	c.1437_1438delAG	p.Arg479SerfsTer8	frameshift	Exon 12 of 17	NP_055761.2
	SPAST	NM_001363823.2		c.1434_1435delAG	p.Arg478SerfsTer8	frameshift	Exon 12 of 17	NP_001350752.1	A0A2U3TZR0
	SPAST	NM_199436.2		c.1341_1342delAG	p.Arg447SerfsTer8	frameshift	Exon 11 of 16	NP_955468.1	E5KRP6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPAST	ENST00000315285.9	TSL:1 MANE Select	c.1437_1438delAG	p.Arg479SerfsTer8	frameshift	Exon 12 of 17	ENSP00000320885.3	Q9UBP0-1
	SPAST	ENST00000621856.2	TSL:1	c.1434_1435delAG	p.Arg478SerfsTer8	frameshift	Exon 12 of 17	ENSP00000482496.2	A0A2U3TZR0
	SPAST	ENST00000713716.1		c.1542_1543delAG	p.Arg514SerfsTer8	frameshift	Exon 13 of 18	ENSP00000519019.1	A0AAQ5BGQ0

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Hereditary spastic paraplegia 4 (3)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.0
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs864622268;

hg19: chr2-32362198;