chr16-89526347-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1PM2PP5

The NM_003119.4(SPG7):​c.637C>T​(p.Arg213Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000434 in 1,613,936 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 Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000045 ( 0 hom. )

Consequence

SPG7
NM_003119.4 stop_gained

Scores

4
2
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:1O:1

Conservation

PhyloP100: 2.76
Variant links:
Genes affected
SPG7 (HGNC:11237): (SPG7 matrix AAA peptidase subunit, paraplegin) This gene encodes a mitochondrial metalloprotease protein that is a member of the AAA 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. Mutations in this gene cause autosomal recessive spastic paraplegia 7. Two transcript variants encoding distinct isoforms have been identified. [provided by RefSeq, Mar 2014]

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 11 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 16-89526347-C-T is Pathogenic according to our data. Variant chr16-89526347-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 285368.We mark this variant Likely_pathogenic, oryginal submissions are: {not_provided=1, Pathogenic=5, Uncertain_significance=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
SPG7NM_003119.4 linkuse as main transcriptc.637C>T p.Arg213Ter stop_gained 5/17 ENST00000645818.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SPG7ENST00000645818.2 linkuse as main transcriptc.637C>T p.Arg213Ter stop_gained 5/17 NM_003119.4 P2Q9UQ90-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152084
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000795
AC:
20
AN:
251492
Hom.:
0
AF XY:
0.0000809
AC XY:
11
AN XY:
135918
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000298
Gnomad EAS exome
AF:
0.000381
Gnomad SAS exome
AF:
0.000131
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000527
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000451
AC:
66
AN:
1461852
Hom.:
0
Cov.:
31
AF XY:
0.0000495
AC XY:
36
AN XY:
727226
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000671
Gnomad4 ASJ exome
AF:
0.000383
Gnomad4 EAS exome
AF:
0.000101
Gnomad4 SAS exome
AF:
0.0000928
Gnomad4 FIN exome
AF:
0.0000187
Gnomad4 NFE exome
AF:
0.0000333
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152084
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74290
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.000288
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000442
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.000115
AC:
14
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 7 Pathogenic:1Uncertain:1Other:1
Pathogenic, criteria provided, single submitterclinical testingInvitaeFeb 05, 2020For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in SPG7 are known to be pathogenic (PMID: 14722615, 16357941). This variant has been observed in combination with another SPG7 variant in an individual with clinical features of hereditary spastic paraplegia (PMID: 30098094). ClinVar contains an entry for this variant (Variation ID: 285368). This variant is present in population databases (rs774774648, ExAC 0.05%). This sequence change creates a premature translational stop signal (p.Arg213*) in the SPG7 gene. It is expected to result in an absent or disrupted protein product. -
not provided, no classification providedphenotyping onlyGenomeConnect, ClinGen-GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 11, 2019The SPG7 c.637C>T (p.Arg213Ter) variant has been reported in one study and is found in one patient with hereditary spastic paraplegia in a compound heterozygous state (Mancini et al. 2019). Control data are unavailable for this variant, which is reported at a frequency of 0.000462 in the East Asian population of the Exome Aggregation Consortium. Based on the limited clinical evidence and the potential impact of stop-gained variants, the p.Arg213Ter variant is classified as a variant of unknown significance but suspicious for pathogenicity for autosomal recessive hereditary spastic paraplegia. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingGeneDxNov 29, 2022Identified in an individual with ataxia who harbored a second pathogenic SPG7 variant (Mancini et al., 2018); Identified in two individuals with cerebellar atrophy, one of whom was described to harbor a second pathogenic SPG7 variant (Lupo et al., 2020); Identified in an individual with sporadic amyotrophic lateral sclerosis (Kruger et al., 2016); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 27790088, 32161564, 30098094, 34374492, 34507444) -
Pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Dec 14, 2015- -
SPG7-related disorder Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesDec 15, 2022The SPG7 c.637C>T variant is predicted to result in premature protein termination (p.Arg213*). This variant has been documented in both the compound heterozygous and heterozygous states in patients with spastic paraplegia 7 (Patient Table S2 in Mancini et al. 2018. PubMed ID: 30098094; Patient CB_3 and CB_4 in Lupo et al. 2020. PubMed ID: 32161564), and found in the compound heterozygous state in a patient with parkinsonism (Bhattacharjee et al. 2021. PubMed ID: 34507444). This variant was also identified in the heterozygous state in a patient with ALS who also had an additional variant in the GARS gene (Patient 385 in Krüger et al. 2016. PubMed ID: 27790088). This variant is reported in 0.038% of alleles in individuals of East Asian descent in gnomAD (http://gnomad.broadinstitute.org/variant/16-89592755-C-T). Nonsense variants in SPG7 are expected to be pathogenic. This variant is interpreted as pathogenic. -
Hereditary spastic paraplegia Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGenome Diagnostics Laboratory, The Hospital for Sick ChildrenApr 01, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.31
D
BayesDel_noAF
Pathogenic
0.52
CADD
Pathogenic
40
DANN
Uncertain
1.0
Eigen
Pathogenic
0.89
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Uncertain
0.82
D
MutationTaster
Benign
1.0
A;A
Vest4
0.92, 0.94
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.19
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.

Other links and lift over

dbSNP: rs774774648; hg19: chr16-89592755; API