22-33316188-G-C

Variant names:

• chr22-33316188-G-C
• rs754744384
• NM_133642.5:c.1348C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_133642.5(LARGE1):​c.1348C>G​(p.Arg450Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,800 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R450H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LARGE1 NM_133642.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.20
• 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

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• 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: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LARGE1	NM_133642.5	MANE Select	c.1348C>G	p.Arg450Gly	missense	Exon 11 of 15	NP_598397.1	O95461-1
	LARGE1	NM_001362949.2		c.1348C>G	p.Arg450Gly	missense	Exon 12 of 16	NP_001349878.1	O95461-1
	LARGE1	NM_001362951.2		c.1348C>G	p.Arg450Gly	missense	Exon 11 of 15	NP_001349880.1	O95461-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LARGE1	ENST00000397394.8	TSL:5 MANE Select	c.1348C>G	p.Arg450Gly	missense	Exon 11 of 15	ENSP00000380549.2	O95461-1
	LARGE1	ENST00000354992.7	TSL:1	c.1348C>G	p.Arg450Gly	missense	Exon 12 of 16	ENSP00000347088.2	O95461-1
	LARGE1	ENST00000402320.6	TSL:1	c.1192C>G	p.Arg398Gly	missense	Exon 10 of 14	ENSP00000385223.1	O95461-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461800 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727206

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

American (AMR) AF: 0.0000224 AC: 1 AN: 44720

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53378

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111976

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.29
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.10
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.64	D
Eigen	Benign	0.19
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.013	T
MetaRNN	Uncertain	0.66	D
MetaSVM	Benign	-0.84	T
PhyloP100		6.2
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-3.0	D
REVEL	Uncertain	0.39
Sift	Benign	0.084	T
Sift4G	Benign	0.10	T
Polyphen		0.010	B
Vest4		0.85
MutPred		0.48		Loss of stability (P = 0.0189)
MVP		0.35
MPC		0.84
ClinPred		0.95	D
GERP RS		5.1
Varity_R		0.48
gMVP		0.76
Mutation Taster		=19/81	disease causing

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: rs754744384; hg19: chr22-33712174; COSMIC: COSV61659079; COSMIC: COSV61659079;