14-77288777-C-T

Variant names:

• chr14-77288777-C-T
• rs190285831
• NM_013382.7:c.1238G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_013382.7(POMT2):​c.1238G>A​(p.Arg413Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000109 in 1,461,570 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R413P) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: POMT2 NM_013382.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.62
• Publications: 10 publications found

Genes affected

POMT2 (HGNC:19743): (protein O-mannosyltransferase 2) The protein encoded by this gene is an O-mannosyltransferase that requires interaction with the product of the POMT1 gene for enzymatic function. The encoded protein is found in the membrane of the endoplasmic reticulum. Defects in this gene are a cause of Walker-Warburg syndrome (WWS).[provided by RefSeq, Oct 2008]

POMT2 Gene-Disease associations (from GenCC):

• muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• myopathy caused by variation in POMT2

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B2

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
• autosomal recessive limb-girdle muscular dystrophy type 2N

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy with cerebellar involvement

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital muscular dystrophy with intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• muscle-eye-brain disease

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr14-77288777-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 3225.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.948

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_013382.7. 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
	POMT2	NM_013382.7	MANE Select	c.1238G>A	p.Arg413Gln	missense	Exon 11 of 21	NP_037514.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	POMT2	ENST00000261534.9	TSL:1 MANE Select	c.1238G>A	p.Arg413Gln	missense	Exon 11 of 21	ENSP00000261534.4	Q9UKY4-1
	POMT2	ENST00000682795.1		c.1238G>A	p.Arg413Gln	missense	Exon 11 of 22	ENSP00000507574.1	A0A804HJN3
	POMT2	ENST00000923942.1		c.1238G>A	p.Arg413Gln	missense	Exon 11 of 22	ENSP00000594001.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251478 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000109 AC: 16 AN: 1461570 Hom.: 0 Cov.: 31 AF XY: 0.00000825 AC XY: 6 AN XY: 727094

African (AFR) AF: 0.0000299 AC: 1 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86234

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53392

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

European-Non Finnish (NFE) AF: 0.0000135 AC: 15 AN: 1111782

Other (OTH) AF: 0.00 AC: 0 AN: 60374

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A2;C3150416:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B2;C3150418:Autosomal recessive limb-girdle muscular dystrophy type 2N (1)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.44
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.72	D
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.93	D
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Uncertain	2.1	M
PhyloP100		7.6
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-3.7	D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.0050	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.78		Gain of catalytic residue at G409 (P = 0.023)
MVP		0.95
MPC		0.48
ClinPred		1.0	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.59
gMVP		0.69
Mutation Taster		=61/39	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: rs190285831; hg19: chr14-77755120;