2-71526295-C-G

Position:

• chr2-71526295-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001130987.2(DYSF):​c.1225C>G​(p.Arg409Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,884 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 Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DYSF NM_001130987.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.31

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a domain C2 3 (size 136) in uniprot entity DYSF_HUMAN there are 42 pathogenic changes around while only 4 benign (91%) in NM_001130987.2
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.849

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DYSF	NM_001130987.2	c.1225C>G	p.Arg409Gly	missense_variant	13/56	ENST00000410020.8	NP_001124459.1
DYSF	NM_003494.4	c.1129C>G	p.Arg377Gly	missense_variant	12/55	ENST00000258104.8	NP_003485.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DYSF	ENST00000410020.8	c.1225C>G	p.Arg409Gly	missense_variant	13/56	1	NM_001130987.2	ENSP00000386881.3
DYSF	ENST00000258104.8	c.1129C>G	p.Arg377Gly	missense_variant	12/55	1	NM_003494.4	ENSP00000258104.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251406 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135886

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461884 Hom.: 0 Cov.: 32 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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000278 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 29, 2024

Variant summary: DYSF c.1129C>G (p.Arg377Gly) results in a non-conservative amino acid change located in the C2 domain (IPR000008) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251406 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1129C>G in individuals affected with Limb-Girdle Muscular Dystrophy, Autosomal Recessive and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.80	.;.;.;.;D;.;.;.;.;.;.
Eigen	Uncertain	0.23
Eigen_PC	Benign	0.11
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.96	D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.34	D
MutationAssessor	Benign	1.8	.;.;L;.;L;.;.;.;.;.;.
PrimateAI	Uncertain	0.66	T
PROVEAN	Pathogenic	-5.2	D;D;D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.66
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.0040	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		0.91
MutPred		0.49		.;.;Loss of methylation at R377 (P = 0.0289);.;Loss of methylation at R377 (P = 0.0289);.;.;.;.;.;.;
MVP		0.86
MPC		0.73
ClinPred		0.99	D
GERP RS		3.5
Varity_R		0.95
gMVP		0.79

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: rs758180890; hg19: chr2-71753425;