rs769602042

chr16-89553805-G-Achr16-89553805-G-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_003119.4(SPG7):c.1948G>A(p.Asp650Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000192 in 1,613,334 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D650Y) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: 𝑓 0.000053 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: SPG7 NM_003119.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5 U:1
• Conservation: PhyloP100: 9.67

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 10 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 chr16-89553805-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1344132.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.962
• PP5: Variant 16-89553805-G-A is Pathogenic according to our data. Variant chr16-89553805-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 220101.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=4, Uncertain_significance=1, Likely_pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SPG7	NM_003119.4	c.1948G>A	p.Asp650Asn	missense_variant	15/17	ENST00000645818.2
SPG7	NM_001363850.1	c.1948G>A	p.Asp650Asn	missense_variant	15/18
SPG7	XM_047434537.1	c.1075G>A	p.Asp359Asn	missense_variant	10/13
SPG7	XM_047434540.1	c.634G>A	p.Asp212Asn	missense_variant	7/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SPG7	ENST00000645818.2	c.1948G>A	p.Asp650Asn	missense_variant	15/17		NM_003119.4	P2

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152220 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000327

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000199 AC: 5 AN: 250772 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135786

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000868

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000884

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000157 AC: 23 AN: 1461114 Hom.: 0 Cov.: 32 AF XY: 0.0000151 AC XY: 11 AN XY: 726874

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000671

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000153

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000526 AC: 8 AN: 152220 Hom.: 0 Cov.: 33 AF XY: 0.0000672 AC XY: 5 AN XY: 74360

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.000327

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000264

ExAC AF: 0.0000165 AC: 2

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:5 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary spastic paraplegia 7 Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Nov 08, 2023	Variant summary: SPG7 c.1948G>A (p.Asp650Asn) results in a conservative amino acid change located in the Peptidase M41 domain (IPR000642) of the encoded protein sequence. Three of four in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 250772 control chromosomes (gnomAD). c.1948G>A has been reported in the literature in multiple individuals affected with Hereditary Spastic Paraplegia 7 and the variant co-segregated with the disease (Fogel_2014, Dela Casa-Fages_2019, Fernndez-Moreno_2020, Charif_2021). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 33841295, 31433872, 32204931, 25133958). Four submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified this variant as uncertain significance (n=1), likely pathogenic (n=1) and pathogenic (n=2). Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 09, 2024	This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 650 of the SPG7 protein (p.Asp650Asn). This variant is present in population databases (rs769602042, gnomAD 0.009%). This missense change has been observed in individual(s) with clinical features of hereditary spastic paraplegia (PMID: 31433872, 32204931; 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. ClinVar contains an entry for this variant (Variation ID: 220101). 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 with a positive predictive value of 80%. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jan 26, 2023	- -

not provided Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Oct 01, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jan 24, 2022	The frequency of this variant in the general population is consistent with pathogenicity (http://gnomad.broadinstitute.org). This variant appears to be associated with disease in at least one family, however, the available information does not rule out an apparent association due to chance. In multiple individuals, this variant has been seen with a single recessive pathogenic variant in the same gene, suggesting this variant may also be pathogenic. Computational tools predict that this variant is damaging. The variant is located in a region that is considered important for protein function and/or structure. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Uncertain	0.053	T
BayesDel_noAF	Uncertain	0.040
Cadd	Pathogenic	31
Dann	Pathogenic	1.0
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.71	T
Polyphen		1.0	.;.;D;.;.;.;.;.;.
MutPred		0.83		.;.;Gain of MoRF binding (P = 0.0325);.;.;.;Gain of MoRF binding (P = 0.0325);.;.;
MVP		0.94
MPC		0.77
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.90
gMVP		0.97

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

LitVar

Other links and lift over

dbSNP: rs769602042; hg19: chr16-89620213; COSMIC: COSV51951109; COSMIC: COSV51951109;