3-49533031-T-G

Variant names:

• chr3-49533031-T-G
• rs149564053
• NM_004393.6:c.2520T>G

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_004393.6(DAG1):​c.2520T>G​(p.Thr840Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,613,588 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. T840T) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DAG1 NM_004393.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.35
• Publications: 0 publications found

Genes affected

DAG1 (HGNC:2666): (dystroglycan 1) This gene encodes dystroglycan, a central component of dystrophin-glycoprotein complex that links the extracellular matrix and the cytoskeleton in the skeletal muscle. The encoded preproprotein undergoes O- and N-glycosylation, and proteolytic processing to generate alpha and beta subunits. Certain mutations in this gene are known to cause distinct forms of muscular dystrophy. Alternative splicing results in multiple transcript variants, all encoding the same protein. [provided by RefSeq, Nov 2015]

DAG1 Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy type 2P

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Genomics England PanelApp, Orphanet
• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A9

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• muscular dystrophy-dystroglycanopathy, type A

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• isolated asymptomatic elevation of creatine phosphokinase

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.75).
• BP7: Synonymous conserved (PhyloP=-1.35 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004393.6. 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
	DAG1	NM_004393.6	MANE Select	c.2520T>G	p.Thr840Thr	synonymous	Exon 3 of 3	NP_004384.5
	DAG1	NM_001165928.4		c.2520T>G	p.Thr840Thr	synonymous	Exon 6 of 6	NP_001159400.3
	DAG1	NM_001177634.3		c.2520T>G	p.Thr840Thr	synonymous	Exon 6 of 6	NP_001171105.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DAG1	ENST00000308775.7	TSL:1 MANE Select	c.2520T>G	p.Thr840Thr	synonymous	Exon 3 of 3	ENSP00000312435.2
	DAG1	ENST00000418588.6	TSL:3	c.2520T>G	p.Thr840Thr	synonymous	Exon 4 of 4	ENSP00000405859.2
	DAG1	ENST00000421560.6	TSL:4	c.2520T>G	p.Thr840Thr	synonymous	Exon 3 of 3	ENSP00000412067.2

Frequencies

GnomAD3 genomes AF: 0.00000659 AC: 1 AN: 151718 Hom.: 0 Cov.: 32

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: 0.00000137 AC: 2 AN: 1461870 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727230

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

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: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000659 AC: 1 AN: 151718 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74084

African (AFR) AF: 0.00 AC: 0 AN: 41240

American (AMR) AF: 0.00 AC: 0 AN: 15244

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5168

South Asian (SAS) AF: 0.00 AC: 0 AN: 4810

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10542

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67924

Other (OTH) AF: 0.00 AC: 0 AN: 2092

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.75
CADD	Benign	3.2
DANN	Benign	0.64
PhyloP100		-1.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs149564053; hg19: chr3-49570464;