rs755660222

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_013382.7(POMT2):​c.678delG​(p.Trp226CysfsTer6) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,884 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

POMT2
NM_013382.7 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 7.82

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A2
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 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 14-77301227-AC-A is Pathogenic according to our data. Variant chr14-77301227-AC-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 211951.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
POMT2
NM_013382.7
MANE Select
c.678delGp.Trp226CysfsTer6
frameshift
Exon 6 of 21NP_037514.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
POMT2
ENST00000261534.9
TSL:1 MANE Select
c.678delGp.Trp226CysfsTer6
frameshift
Exon 6 of 21ENSP00000261534.4
POMT2
ENST00000556326.5
TSL:1
n.*344delG
non_coding_transcript_exon
Exon 5 of 6ENSP00000450630.1
POMT2
ENST00000556326.5
TSL:1
n.*344delG
3_prime_UTR
Exon 5 of 6ENSP00000450630.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251314
AF XY:
0.0000147
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461884
Hom.:
0
Cov.:
32
AF XY:
0.0000124
AC XY:
9
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
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:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000162
AC:
18
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

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 Pathogenic:1
Sep 24, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Trp226Cysfs*6) in the POMT2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in POMT2 are known to be pathogenic (PMID: 15894594). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 211951). This variant has not been reported in the literature in individuals affected with POMT2-related conditions. This variant is present in population databases (rs755660222, gnomAD 0.0009%).

Muscular dystrophy Pathogenic:1
Mar 04, 2015
Genetic Services Laboratory, University of Chicago
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A2 Pathogenic:1
Jan 16, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
PhyloP100
7.8
Mutation Taster
=1/199
disease causing (ClinVar)

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

Publications

Other links and lift over

dbSNP: rs755660222; hg19: chr14-77767570; API