NM_025137.4:c.1551_1552delTT

Variant names:

• chr15-44648915-CAA-C
• rs312262730
• NM_025137.4:c.1551_1552delTT

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_025137.4(SPG11):​c.1551_1552delTT​(p.Cys518SerfsTer39) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,832 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SPG11 NM_025137.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 7.36
• Publications: 3 publications found

Genes affected

SPG11 (HGNC:11226): (SPG11 vesicle trafficking associated, spatacsin) The protein encoded by this gene is a potential transmembrane protein that is phosphorylated upon DNA damage. Defects in this gene are a cause of spastic paraplegia type 11 (SPG11). Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2009]

SPG11 Gene-Disease associations (from GenCC):

• hereditary spastic paraplegia 11

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Illumina, G2P
• amyotrophic lateral sclerosis type 5

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• Charcot-Marie-Tooth disease axonal type 2X

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp
• juvenile amyotrophic lateral sclerosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 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 15-44648915-CAA-C is Pathogenic according to our data. Variant chr15-44648915-CAA-C is described in ClinVar as Pathogenic. ClinVar VariationId is 41275.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_025137.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPG11	NM_025137.4	MANE Select	c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 40	NP_079413.3
	SPG11	NM_001411132.1		c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 40	NP_001398061.1
	SPG11	NM_001160227.2		c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 38	NP_001153699.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SPG11	ENST00000261866.12	TSL:1 MANE Select	c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 40	ENSP00000261866.7
	SPG11	ENST00000535302.6	TSL:1	c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 38	ENSP00000445278.2
	SPG11	ENST00000427534.6	TSL:1	c.1551_1552delTT	p.Cys518SerfsTer39	frameshift	Exon 7 of 37	ENSP00000396110.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461832 Hom.: 0 AF XY: 0.00000138 AC XY: 1 AN XY: 727220

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111982

Other (OTH) AF: 0.0000166 AC: 1 AN: 60394

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0000343967), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 11 Pathogenic:1 Other:1

Aug 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Cys518Serfs*39) in the SPG11 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SPG11 are known to be pathogenic (PMID: 19105190, 20110243, 22154821, 26556829). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with hereditary spastic paraplegia (PMID: 18663179). This variant is also known as c.1550_1551delTT (p.L517fsX556). ClinVar contains an entry for this variant (Variation ID: 41275). For these reasons, this variant has been classified as Pathogenic.

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.4
Mutation Taster		=1/199	disease causing (fs/PTC)

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

Other links and lift over

dbSNP: rs312262730; hg19: chr15-44941113;