NM_014946.4:c.1507C>T

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_014946.4(SPAST):​c.1507C>T​(p.Arg503Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,459,340 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R503Q) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

SPAST
NM_014946.4 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 3.41

Publications

6 publications found
Variant links:
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: Orphanet, Labcorp Genetics (formerly Invitae), Illumina, Genomics England PanelApp, 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain in NM_014946.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-32141918-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1992311.Status of the report is criteria_provided_single_submitter, 1 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 148 curated pathogenic missense variants (we use a threshold of 10). The gene has 21 curated benign missense variants. Gene score misZ: 1.2438 (below the threshold of 3.09). Trascript score misZ: 0.22274 (below the threshold of 3.09). GenCC associations: The gene is linked to hereditary spastic paraplegia 4, SPAST-related motor disorder, Charlevoix-Saguenay spastic ataxia, neurodevelopmental disorder.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.986
PP5
Variant 2-32141917-C-T is Pathogenic according to our data. Variant chr2-32141917-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 219575.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SPASTNM_014946.4 linkc.1507C>T p.Arg503Trp missense_variant Exon 13 of 17 ENST00000315285.9 NP_055761.2 Q9UBP0-1E5KRP5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPASTENST00000315285.9 linkc.1507C>T p.Arg503Trp missense_variant Exon 13 of 17 1 NM_014946.4 ENSP00000320885.3 Q9UBP0-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000399
AC:
1
AN:
250512
AF XY:
0.00
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 FIN exome
AF:
0.0000464
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000206
AC:
3
AN:
1459340
Hom.:
0
Cov.:
30
AF XY:
0.00
AC XY:
0
AN XY:
726008
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33416
American (AMR)
AF:
0.00
AC:
0
AN:
44636
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26090
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39548
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85844
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53172
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5614
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1110732
Other (OTH)
AF:
0.00
AC:
0
AN:
60288
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 4 Pathogenic:5
Feb 28, 2019
Codex Genetics Limited
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:provider interpretation

- -

Oct 31, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 219575). For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Arg503 amino acid residue in SPAST. Other variant(s) that disrupt this residue have been observed in individuals with SPAST-related conditions (PMID: 12552568, 26374131), which suggests that this may be a clinically significant amino acid residue. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SPAST protein function. This missense change has been observed in individuals with hereditary spastic paraplegia (PMID: 16055926, 17594340, 18701882, 20932283). This variant is present in population databases (no rsID available, gnomAD 0.005%). This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 503 of the SPAST protein (p.Arg503Trp). -

Feb 23, 2023
3billion
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). The variant is located in a mutational hot spot and/or well-established functional domain in which established pathogenic variants have been reported. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.92; 3Cnet: 0.99). Same nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000219575). Different missense changes at the same codon (p.Arg503Leu, p.Arg503Pro) have been reported to be associated with SPAST related disorder (PMID: 12552568, 26374131). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -

Jan 17, 2022
MGZ Medical Genetics Center
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 27, 2023
Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL)
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Pathogenic:2
Mar 17, 2022
Athena Diagnostics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The frequency of this variant in the general population is consistent with pathogenicity (http://gnomad.broadinstitute.org). This variant has been identified in multiple unrelated individuals with clinical features associated with this gene. Computational tools predict that this variant is damaging. -

Oct 01, 2017
CeGaT Center for Human Genetics Tuebingen
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary spastic paraplegia Pathogenic:1
Dec 12, 2016
Genome Diagnostics Laboratory, The Hospital for Sick Children
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.48
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.95
D;D;.;.;.;.;.;.
Eigen
Pathogenic
0.74
Eigen_PC
Pathogenic
0.68
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Pathogenic
0.99
.;D;D;.;D;D;D;D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Uncertain
2.5
M;M;.;.;.;.;.;.
PhyloP100
3.4
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-8.0
D;.;D;.;.;.;.;.
REVEL
Pathogenic
0.92
Sift
Pathogenic
0.0
D;.;D;.;.;.;.;.
Sift4G
Pathogenic
0.0
D;D;D;.;.;.;.;.
Polyphen
1.0
D;D;.;.;.;.;.;.
Vest4
0.93
MutPred
0.94
Loss of MoRF binding (P = 0.0574);Loss of MoRF binding (P = 0.0574);.;.;.;.;.;.;
MVP
0.99
MPC
2.2
ClinPred
1.0
D
GERP RS
5.1
Varity_R
0.97
gMVP
0.95
Mutation Taster
=0/100
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs864622162; hg19: chr2-32366986; COSMIC: COSV100188499; API