16-89553853-G-C

Variant summary

Our verdict is Pathogenic. The variant received 26 ACMG points: 26P and 0B. PS1_Very_StrongPM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_003119.4(SPG7):​c.1996G>C​(p.Gly666Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,424 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G666V) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

SPG7
NM_003119.4 missense

Scores

13
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.84

Publications

1 publications found
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]
SPG7 Gene-Disease associations (from GenCC):
  • hereditary spastic paraplegia 7
    Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
  • lateral sclerosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 26 ACMG points.

PS1
Transcript NM_003119.4 (SPG7) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 217271
PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_003119.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr16-89553854-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 803288.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.952
PP5
Variant 16-89553853-G-C is Pathogenic according to our data. Variant chr16-89553853-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 216571.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
SPG7NM_003119.4 linkc.1996G>C p.Gly666Arg missense_variant Exon 15 of 17 ENST00000645818.2 NP_003110.1 Q9UQ90-1
SPG7NM_001363850.1 linkc.1996G>C p.Gly666Arg missense_variant Exon 15 of 18 NP_001350779.1
SPG7XM_047434537.1 linkc.1123G>C p.Gly375Arg missense_variant Exon 10 of 13 XP_047290493.1
SPG7XM_047434540.1 linkc.682G>C p.Gly228Arg missense_variant Exon 7 of 9 XP_047290496.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SPG7ENST00000645818.2 linkc.1996G>C p.Gly666Arg missense_variant Exon 15 of 17 NM_003119.4 ENSP00000495795.2 Q9UQ90-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152260
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
250942
AF XY:
0.0000147
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:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1461164
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
726900
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52718
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111992
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
0
1
1
2
2
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
AF:
0.00000657
AC:
1
AN:
152260
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74386
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41476
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10632
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary spastic paraplegia 7 Pathogenic:2
Oct 13, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is present in population databases (rs752989523, gnomAD 0.002%). For these reasons, this variant has been classified as Pathogenic. 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 SPG7 protein function. ClinVar contains an entry for this variant (Variation ID: 216571). This missense change has been observed in individual(s) with hereditary spastic paraplegia (PMID: 23733235; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 666 of the SPG7 protein (p.Gly666Arg). -

Jan 01, 2022
PROSPAX: an integrated multimodal progression chart in spastic ataxias, Center for Neurology; Hertie-Institute for Clinical Brain Research
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

not provided Pathogenic:2
Apr 26, 2023
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Reported previously, along with a second variant, in individuals with spastic paraplegia (Yoon et al., 2013).; This variant is associated with the following publications: (PMID: 23733235, 22571692) -

Sep 25, 2022
Genetic Services Laboratory, University of Chicago
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

DNA sequence analysis of the SPG7 gene demonstrated a sequence change, c.1996G>C, in exon 15 that results in an amino acid change, p.Gly666Arg. The p.Gly666Arg change affects a highly conserved amino acid residue located in a domain of the SPG7 protein that is known to be functional. The p.Gly666Arg substitution appears to be deleterious using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). This particular amino acid change has been described in the literature in trans with a pathogenic variant in two individuals with spastic paraplegia (PMID: 23733235). This sequence change has been described in the gnomAD database with a frequency of 0.0008% in the overall population (dbSNP rs752989523). These collective evidences indicate that this sequence change is likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.57
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.92
.;.;D;.;.;.;.;.;.
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.96
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.93
D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.80
D
MetaRNN
Pathogenic
0.95
D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.4
.;.;H;.;.;.;.;.;.
PhyloP100
7.8
PrimateAI
Uncertain
0.68
T
REVEL
Pathogenic
0.98
Polyphen
1.0
.;.;D;.;.;.;.;.;.
MutPred
0.87
.;.;Gain of MoRF binding (P = 0.0183);.;.;.;Gain of MoRF binding (P = 0.0183);.;.;
MVP
0.98
MPC
0.73
ClinPred
1.0
D
GERP RS
5.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.95
gMVP
0.95
Mutation Taster
=4/96
disease causing (ClinVar)

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

Publications

Other links and lift over

dbSNP: rs752989523; hg19: chr16-89620261; API