3-49510406-CTTT-CTTTTT

Variant names:

• chr3-49510406-C-CTT
• rs200455639
• NM_004393.6:c.-116-5_-116-4dupTT

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_004393.6(DAG1):​c.-116-5_-116-4dupTT variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000142 in 773,924 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: DAG1 NM_004393.6 splice_region, intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.648
• 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: Orphanet, Genomics England PanelApp, G2P
• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A9

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• 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: Uncertain_significance. The variant received 0 ACMG points.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DAG1	NM_004393.6	MANE Select	c.-116-5_-116-4dupTT		splice_region intron	N/A	NP_004384.5	Q14118
	DAG1	NM_001165928.4		c.-116-5_-116-4dupTT		splice_region intron	N/A	NP_001159400.3	Q14118
	DAG1	NM_001177634.3		c.-116-5_-116-4dupTT		splice_region intron	N/A	NP_001171105.2	Q14118

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DAG1	ENST00000308775.7	TSL:1 MANE Select	c.-116-5_-116-4dupTT		splice_region intron	N/A	ENSP00000312435.2	Q14118
	DAG1	ENST00000479935.1	TSL:1	n.191_192dupTT		non_coding_transcript_exon	Exon 1 of 2
	DAG1	ENST00000418588.6	TSL:3	c.-116-5_-116-4dupTT		splice_region intron	N/A	ENSP00000405859.2	Q14118

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000142 AC: 11 AN: 773924 Hom.: 0 Cov.: 11 AF XY: 0.0000171 AC XY: 7 AN XY: 409480

⚠️ 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: 20098

American (AMR) AF: 0.00 AC: 0 AN: 39952

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 20858

East Asian (EAS) AF: 0.00 AC: 0 AN: 36326

South Asian (SAS) AF: 0.00 AC: 0 AN: 70344

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 38028

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 2796

European-Non Finnish (NFE) AF: 0.0000217 AC: 11 AN: 507752

Other (OTH) AF: 0.00 AC: 0 AN: 37770

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.65

Splicing

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

Other links and lift over

dbSNP: rs200455639; hg19: chr3-49547839;