rs1553522104

Variant names:

• chr2-71516180-ACT-A
• rs1553522104
• NM_001130987.2:c.892_893delCT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001130987.2(DYSF):​c.892_893delCT​(p.Leu298PhefsTer6) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,874 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: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DYSF NM_001130987.2 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 2.92

Genes affected

DYSF (HGNC:3097): (dysferlin) The protein encoded by this gene belongs to the ferlin family and is a skeletal muscle protein found associated with the sarcolemma. It is involved in muscle contraction and contains C2 domains that play a role in calcium-mediated membrane fusion events, suggesting that it may be involved in membrane regeneration and repair. In addition, the protein encoded by this gene binds caveolin-3, a skeletal muscle membrane protein which is important in the formation of caveolae. Specific mutations in this gene have been shown to cause autosomal recessive limb girdle muscular dystrophy type 2B (LGMD2B) as well as Miyoshi myopathy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 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 2-71516180-ACT-A is Pathogenic according to our data. Variant chr2-71516180-ACT-A is described in ClinVar as [Pathogenic]. Clinvar id is 555171.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-71516180-ACT-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DYSF	NM_001130987.2	c.892_893delCT	p.Leu298PhefsTer6	frameshift_variant	Exon 9 of 56	ENST00000410020.8	NP_001124459.1
DYSF	NM_003494.4	c.796_797delCT	p.Leu266PhefsTer6	frameshift_variant	Exon 8 of 55	ENST00000258104.8	NP_003485.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DYSF	ENST00000410020.8	c.892_893delCT	p.Leu298PhefsTer6	frameshift_variant	Exon 9 of 56	1	NM_001130987.2	ENSP00000386881.3
DYSF	ENST00000258104.8	c.796_797delCT	p.Leu266PhefsTer6	frameshift_variant	Exon 8 of 55	1	NM_003494.4	ENSP00000258104.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461874 Hom.: 0 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Nov 01, 2022

Revvity Omics, Revvity

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2B Pathogenic:1

Nov 21, 2017

Counsyl

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Miyoshi muscular dystrophy 1 Pathogenic:1

Nov 10, 2021

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Qualitative or quantitative defects of dysferlin Pathogenic:1

Feb 14, 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.Leu266Phefs*6) in the DYSF gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in DYSF are known to be pathogenic (PMID: 17698709, 20301480). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with DYSF-related conditions (PMID: 17897828, 33250842, 33610434). This variant is also known as g.794_795delCT (Thr265fsX271); p.Leu298fs. ClinVar contains an entry for this variant (Variation ID: 555171). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

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: rs1553522104; hg19: chr2-71743310;