22-33432294-T-C

Variant names:

• chr22-33432294-T-C
• rs147579402
• NM_133642.5:c.788-29A>G

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_133642.5(LARGE1):​c.788-29A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00678 in 1,565,854 control chromosomes in the GnomAD database, including 48 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). There are indicators that this mutation may affect the branch point..

• Frequency:
  • Genomes: 𝑓 0.0055 (7 hom., cov: 32)
  • Exomes 𝑓: 0.0069 (41 hom.)
• Consequence: LARGE1 NM_133642.5 intron
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 0.0160
• Publications: 0 publications found

Genes affected

LARGE1 (HGNC:6511): (LARGE xylosyl- and glucuronyltransferase 1) This gene encodes a member of the N-acetylglucosaminyltransferase gene family. It encodes a glycosyltransferase which participates in glycosylation of alpha-dystroglycan, and may carry out the synthesis of glycoprotein and glycosphingolipid sugar chains. It may also be involved in the addition of a repeated disaccharide unit. The protein encoded by this gene is the glycotransferase that adds the final xylose and glucuronic acid to alpha-dystroglycan and thereby allows alpha-dystroglycan to bind ligands including laminin 211 and neurexin. Mutations in this gene cause several forms of congenital muscular dystrophy characterized by cognitive disability and abnormal glycosylation of alpha-dystroglycan. Alternative splicing of this gene results in multiple transcript variants that encode the same protein. [provided by RefSeq, May 2018]

LARGE1 Gene-Disease associations (from GenCC):

• muscular dystrophy-dystroglycanopathy type B6

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A6

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp
• congenital muscular dystrophy with intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• muscular dystrophy-dystroglycanopathy, type A

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Benign. The variant received -20 ACMG points.

• BP4: This position, referring to a specific DNA site, is a probable branch point but is likely benign (scored 1 / 10, using the threshold of <=3). The score ranges from 0 to 10, with values ≤3 considered benign and >5 classified as pathogenic. Computational evidence support a benign effect (BayesDel_noAF=-0.81).
• BP6: Variant 22-33432294-T-C is Benign according to our data. Variant chr22-33432294-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 259536.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00545 (830/152226) while in subpopulation NFE AF = 0.00835 (568/68006). AF 95% confidence interval is 0.00778. There are 7 homozygotes in GnomAd4. There are 407 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 7 AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_133642.5. 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
	LARGE1	NM_133642.5	MANE Select	c.788-29A>G		intron	N/A	NP_598397.1
	LARGE1	NM_001362949.2		c.788-29A>G		intron	N/A	NP_001349878.1
	LARGE1	NM_001362951.2		c.788-29A>G		intron	N/A	NP_001349880.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LARGE1	ENST00000397394.8	TSL:5 MANE Select	c.788-29A>G		intron	N/A	ENSP00000380549.2
	LARGE1	ENST00000354992.7	TSL:1	c.788-29A>G		intron	N/A	ENSP00000347088.2
	LARGE1	ENST00000402320.6	TSL:1	c.788-29A>G		intron	N/A	ENSP00000385223.1

Frequencies

GnomAD3 genomes AF: 0.00546 AC: 830 AN: 152108 Hom.: 7 Cov.: 32

Gnomad AFR AF: 0.00138

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00203

Gnomad ASJ AF: 0.00231

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000415

Gnomad FIN AF: 0.0144

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00835

Gnomad OTH AF: 0.00526

GnomAD2 exomes AF: 0.00590 AC: 1472 AN: 249682 AF XY: 0.00594

Gnomad AFR exome AF: 0.00124

Gnomad AMR exome AF: 0.00160

Gnomad ASJ exome AF: 0.00249

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0170

Gnomad NFE exome AF: 0.00836

Gnomad OTH exome AF: 0.00654

GnomAD4 exome AF: 0.00692 AC: 9784 AN: 1413628 Hom.: 41 Cov.: 24 AF XY: 0.00671 AC XY: 4738 AN XY: 706342

African (AFR) AF: 0.00114 AC: 37 AN: 32534

American (AMR) AF: 0.00186 AC: 83 AN: 44614

Ashkenazi Jewish (ASJ) AF: 0.00244 AC: 63 AN: 25828

East Asian (EAS) AF: 0.00 AC: 0 AN: 39454

South Asian (SAS) AF: 0.000610 AC: 52 AN: 85182

European-Finnish (FIN) AF: 0.0161 AC: 858 AN: 53294

Middle Eastern (MID) AF: 0.000529 AC: 3 AN: 5666

European-Non Finnish (NFE) AF: 0.00779 AC: 8326 AN: 1068294

Other (OTH) AF: 0.00616 AC: 362 AN: 58762

GnomAD4 genome AF: 0.00545 AC: 830 AN: 152226 Hom.: 7 Cov.: 32 AF XY: 0.00547 AC XY: 407 AN XY: 74434

African (AFR) AF: 0.00137 AC: 57 AN: 41540

American (AMR) AF: 0.00203 AC: 31 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00231 AC: 8 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.000415 AC: 2 AN: 4820

European-Finnish (FIN) AF: 0.0144 AC: 153 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00835 AC: 568 AN: 68006

Other (OTH) AF: 0.00521 AC: 11 AN: 2112

Alfa AF: 0.00720 Hom.: 3

Bravo AF: 0.00412

Asia WGS AF: 0.00144 AC: 5 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Jul 08, 2018

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Breakthrough Genomics, Breakthrough Genomics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: not provided

not specified Benign:1

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	6.8
DANN	Benign	0.76
PhyloP100		0.016
La Branchor		0.57
BranchPoint Hunter		1.0
Mutation Taster		=100/0	polymorphism

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: rs147579402; hg19: chr22-33828280;