2-71568318-G-C

Position:

• chr2-71568318-G-C

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_001130987.2(DYSF):​c.2844G>C​(p.Trp948Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: DYSF NM_001130987.2 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4 U:2
• Conservation: PhyloP100: 7.93

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 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993
• PP5: Variant 2-71568318-G-C is Pathogenic according to our data. Variant chr2-71568318-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 167021.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-71568318-G-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DYSF	NM_001130987.2	c.2844G>C	p.Trp948Cys	missense_variant	26/56	ENST00000410020.8	NP_001124459.1
DYSF	NM_003494.4	c.2790G>C	p.Trp930Cys	missense_variant	26/55	ENST00000258104.8	NP_003485.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DYSF	ENST00000410020.8	c.2844G>C	p.Trp948Cys	missense_variant	26/56	1	NM_001130987.2	ENSP00000386881	A1
DYSF	ENST00000258104.8	c.2790G>C	p.Trp930Cys	missense_variant	26/55	1	NM_003494.4	ENSP00000258104	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4 Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Qualitative or quantitative defects of dysferlin Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 17, 2023	This sequence change replaces tryptophan, which is neutral and slightly polar, with cysteine, which is neutral and slightly polar, at codon 930 of the DYSF protein (p.Trp930Cys). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with DYSF-related conditions (PMID: 18853459, 33610434). ClinVar contains an entry for this variant (Variation ID: 167021). 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 DYSF protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	research	Jain Foundation	Mar 13, 2023	This variant is absent from gnomAD v2.1.1. This variant has been reported in individuals with a clinical phenotype consistent with dysferlinopathy, associated with disease range dysferlin protein levels, and found in the heterozygous state in conjuction with the pathogeic or likely pathogenic DYSF variants, c.2643+1G>A, c.4024C>T, or c.3832C>T (PMID: 36983702, 18853459). This variant has also been reported to cause reduced dysferlin protein expression and no plasma membrane localization via an in vitro assay (PMID: 35028538). Both the REVEL (0.867) and CADD (25.7) scores support a deleterious effect. The ACMG classification criteria applied are: PM2 moderate, PM3 moderate, PP3, PP4 moderate, and PS3 supporting. Based on the above data, this variant has been classified as Likely Pathogenic. -

not provided Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Sep 18, 2023	- -
Uncertain significance, flagged submission	clinical testing	Eurofins Ntd Llc (ga)	Feb 05, 2016	- -

Miyoshi muscular dystrophy 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 09, 2023

- -

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

Uncertain significance, flagged submission

clinical testing

Counsyl

Aug 03, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.40
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.89	.;.;.;.;D;.;.;.;.;.;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.58	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.64	D
MutationAssessor	Uncertain	2.9	.;.;M;.;M;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-12	D;D;D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.015	D;D;D;D;D;D;D;D;D;D;D
Polyphen		1.0	D;D;D;D;D;D;D;D;D;D;D
Vest4		0.98
MutPred		0.92		.;.;Loss of sheet (P = 0.0084);.;Loss of sheet (P = 0.0084);.;.;.;.;.;.;
MVP		0.93
MPC		0.82
ClinPred		1.0	D
GERP RS		4.1
Varity_R		0.93
gMVP		0.94

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: rs727503910; hg19: chr2-71795448;