rs587780423

Positions:

chr14-77299497-T-C

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The ENST00000261534.9(POMT2):c.881A>G(p.Tyr294Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,614,010 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

POMT2
ENST00000261534.9 missense

Scores

Clinical Significance

Likely pathogenic criteria provided, multiple submitters, no conflicts P:4U:1

Conservation

PhyloP100: 7.25

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1

In a transmembrane_region Helical (size 20) in uniprot entity POMT2_HUMAN there are 7 pathogenic changes around while only 1 benign (88%) in ENST00000261534.9

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.991

PP5

Variant 14-77299497-T-C is Pathogenic according to our data. Variant chr14-77299497-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 130017.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr14-77299497-T-C is described in Lovd as [Likely_pathogenic]. Variant chr14-77299497-T-C is described in Lovd as [Likely_pathogenic]. Variant chr14-77299497-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POMT2	NM_013382.7 linkuse as main transcript	c.881A>G	p.Tyr294Cys	missense_variant	7/21	ENST00000261534.9	NP_037514.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POMT2	ENST00000261534.9 linkuse as main transcript	c.881A>G	p.Tyr294Cys	missense_variant	7/21	1	NM_013382.7	ENSP00000261534	P1	Q9UKY4-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152152

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251434

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135882

show subpopulations

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000479

AC:

AN:

1461858

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727232

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152152

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74328

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000329

Hom.:

Bravo

AF:

0.0000227

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:4Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:1Uncertain:1

Uncertain significance, flagged submission	clinical testing	Revvity Omics, Revvity	Nov 10, 2022	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 15, 2017	A likely pathogenic variant has been identified in the POMT2 gene. The Y294C variant has recently been reported in the homozygous state in multiple individuals with hypotonia, scoliosis, intellectual disability, and hyperdontia in a consanguineous family in the published literature (Riazuddin et al., 2016). It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The Y294C variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species, and in silico analysis predicts this variant is probably damaging to the protein structure/function. However, missense variants in nearby residues have not been reported in the Human Gene Mutation Database in association with POMT2-related disorders (Stenson et al., 2014). Therefore, the R294C variant is now classified as a likely pathogenic variant. -

Autosomal recessive limb-girdle muscular dystrophy

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Oct 19, 2021

Variant summary: POMT2 c.881A>G (p.Tyr294Cys) results in a non-conservative amino acid change located in the Glycosyl transferase family 39/83 domain (IPR003342) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251434 control chromosomes (gnomAD). c.881A>G has been reported in the literature in at least one individual affected with Limb-Girdle Muscular Dystrophy, Autosomal Recessive (Song_2021). Furthermore, the variant was reported in 4 homozygous individuals from a consanguineous family with features of moderate to severe intellectual disability with speech delay, hyperdontia, moderate hypotonia and scoliosis (Riazuddin_2017). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. A ClinVar submitter (evaluation after 2014) cites the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Autosomal recessive limb-girdle muscular dystrophy type 2N

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Feb 18, 2014

- -

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

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Oct 24, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.65

BayesDel_addAF

Pathogenic

0.47

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.92

Eigen

Pathogenic

0.97

Eigen_PC

Pathogenic

0.88

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

M_CAP

Pathogenic

0.39

MetaRNN

Pathogenic

0.99

MetaSVM

Pathogenic

0.99

MutationAssessor

Pathogenic

4.0

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.65

PROVEAN

Pathogenic

-8.7

REVEL

Pathogenic

0.94

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.98

MVP

0.98

MPC

0.51

ClinPred

1.0

GERP RS

5.5

Varity_R

0.95

gMVP

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over