2-71667478-G-C

Variant names:

• chr2-71667478-G-C
• rs148860301
• NM_001130987.2:c.5420G>C

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2 PM5 PP3_Moderate PP5_Very_Strong

The NM_001130987.2(DYSF):​c.5420G>C​(p.Arg1807Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,846 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1807Q) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DYSF NM_001130987.2 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 10.0
• Publications: 6 publications found

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]

DYSF Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• neuromuscular disease caused by qualitative or quantitative defects of dysferlin

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
• autosomal recessive limb-girdle muscular dystrophy type 2B

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
• distal myopathy with anterior tibial onset

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• congenital myopathy, Paradas type

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Miyoshi myopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-71667478-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 282624.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.876
• PP5: Variant 2-71667478-G-C is Pathogenic according to our data. Variant chr2-71667478-G-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1991591.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001130987.2. 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
	DYSF	NM_001130987.2	MANE Select	c.5420G>C	p.Arg1807Pro	missense	Exon 48 of 56	NP_001124459.1
	DYSF	NM_003494.4	MANE Plus Clinical	c.5303G>C	p.Arg1768Pro	missense	Exon 47 of 55	NP_003485.1
	DYSF	NM_001130981.2		c.5417G>C	p.Arg1806Pro	missense	Exon 48 of 56	NP_001124453.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DYSF	ENST00000410020.8	TSL:1 MANE Select	c.5420G>C	p.Arg1807Pro	missense	Exon 48 of 56	ENSP00000386881.3
	DYSF	ENST00000258104.8	TSL:1 MANE Plus Clinical	c.5303G>C	p.Arg1768Pro	missense	Exon 47 of 55	ENSP00000258104.3
	DYSF	ENST00000409582.7	TSL:1	c.5417G>C	p.Arg1806Pro	missense	Exon 48 of 56	ENSP00000386547.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251176 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461846 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727218

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

American (AMR) AF: 0.0000224 AC: 1 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

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: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5742

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Distal myopathy with anterior tibial onset;C1850889:Autosomal recessive limb-girdle muscular dystrophy type 2B;C4551973:Miyoshi muscular dystrophy 1 Pathogenic:1

Jun 11, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Neuromuscular disease caused by qualitative or quantitative defects of dysferlin Pathogenic:1

Nov 24, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 1768 of the DYSF protein (p.Arg1768Pro). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with DYSF-related conditions. ClinVar contains an entry for this variant (Variation ID: 1991591). 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%. This variant disrupts the p.Arg1768 amino acid residue in DYSF. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 17070050, 17698709, 18853459, 25591676, 25783436, 27647186). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Pathogenic	0.90	D
MutationAssessor	Pathogenic	3.4	M
PhyloP100		10
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-6.2	D
REVEL	Pathogenic	0.89
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.50		Gain of glycosylation at R1768 (P = 0.0419)
MVP		0.97
MPC		0.78
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.88
gMVP		0.98
Mutation Taster		=0/100	disease causing

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: rs148860301; hg19: chr2-71894608;