rs730882237

Variant names:

• chr11-66346724-C-CAA
• rs730882237
• NM_006876.3:c.821_822insTT

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_006876.3(B4GAT1):​c.821_822insTT​(p.Glu274AspfsTer94) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: B4GAT1 NM_006876.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic no assertion criteria provided P:2
• Conservation: PhyloP100: 7.55
• Publications: 1 publications found

Genes affected

B4GAT1 (HGNC:15685): (beta-1,4-glucuronyltransferase 1) This gene encodes a member of the beta-1,3-N-acetylglucosaminyltransferase family. This enzyme is a type II transmembrane protein. It is essential for the synthesis of poly-N-acetyllactosamine, a determinant for the blood group i antigen. [provided by RefSeq, Jul 2008]

B4GAT1 Gene-Disease associations (from GenCC):

• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A13

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-66346724-C-CAA is Pathogenic according to our data. Variant chr11-66346724-C-CAA is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 183334.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006876.3. 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
	B4GAT1	NM_006876.3	MANE Select	c.821_822insTT	p.Glu274AspfsTer94	frameshift	Exon 1 of 2	NP_006867.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	B4GAT1	ENST00000311181.5	TSL:1 MANE Select	c.821_822insTT	p.Glu274AspfsTer94	frameshift	Exon 1 of 2	ENSP00000309096.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic/Likely pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1 (1)
1	-	-	Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A13 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		7.5
Mutation Taster		=6/194	disease causing (ClinVar)

Splicing

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

Other links and lift over

dbSNP: rs730882237; hg19: chr11-66114195;