rs121908962

Positions:

• chr2-71551073-G-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2 PP3_Moderate PP5_Very_Strong

The NM_001130987.2(DYSF):​c.1609G>A​(p.Gly537Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/25 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: DYSF NM_001130987.2 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4 U:1
• Conservation: PhyloP100: 10.0

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 12 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.904
• PP5: Variant 2-71551073-G-A is Pathogenic according to our data. Variant chr2-71551073-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 6679.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-71551073-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DYSF	NM_001130987.2	c.1609G>A	p.Gly537Arg	missense_variant	18/56	ENST00000410020.8	NP_001124459.1
DYSF	NM_003494.4	c.1555G>A	p.Gly519Arg	missense_variant	18/55	ENST00000258104.8	NP_003485.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DYSF	ENST00000410020.8	c.1609G>A	p.Gly537Arg	missense_variant	18/56	1	NM_001130987.2	ENSP00000386881.3
DYSF	ENST00000258104.8	c.1555G>A	p.Gly519Arg	missense_variant	18/55	1	NM_003494.4	ENSP00000258104.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152144 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461850 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 727234

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152144 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74326

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000680 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2 Uncertain:1

Pathogenic, no assertion criteria provided	reference population	Department of Neurology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology	Jul 01, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Sep 26, 2016	The c.1555 G>A pathogenic variant in the DYSF gene has been previously reported in the homozygous state in two siblings with Miyoshi myopathy and absent dysferlin expression on Western blot. Additionally, it was observed in the heterozygous state in their father with calf myalgias and progressive difficulty with walking (Illa et al., 2007). Functional studies demonstrate the c.1555 G>A variant creates a new splice acceptor site resulting in an out-of-frame deletion of 35 base pairs in exon 18 (De Luna et al., 2007; Kergourlay et al., 2014). This variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. -
Uncertain significance, flagged submission	clinical testing	Eurofins Ntd Llc (ga)	Jul 02, 2015	- -

Miyoshi muscular dystrophy 1 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Apr 17, 2007

- -

Qualitative or quantitative defects of dysferlin Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 26, 2019

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. Experimental studies have shown that this variant disrupts mRNA splicing (PMID: 25312915). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has been observed to be homozygous or in combination with another DYSF variant in individuals affected with distal myopathy (PMID: 17287450, 30107846). In at least one individual the data is consistent with the variant being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 6679). This variant is not present in population databases (ExAC no frequency). This sequence change replaces glycine with arginine at codon 519 of the DYSF protein (p.Gly519Arg). The glycine residue is moderately conserved and there is a moderate physicochemical difference between glycine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	35
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.81	.;.;.;.;D;.;.;.;.;.;.
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.30	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	3.9	.;.;H;.;H;.;.;.;.;.;.
PrimateAI	Pathogenic	0.80	D
PROVEAN	Pathogenic	-7.2	D;D;D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	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		0.56		.;.;Loss of sheet (P = 0.0817);.;Loss of sheet (P = 0.0817);.;.;.;.;.;.;
MVP		0.98
MPC		0.71
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.89
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.99		Position offset: 2
DS_AL_spliceai		0.48		Position offset: -32

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs121908962; hg19: chr2-71778203;