NM_032237.5:c.43dupC

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_032237.5(POMK):c.43dupC(p.Arg15ProfsTer85) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000142 in 1,614,044 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

POMK
NM_032237.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: -1.29

Variant links:

Genes affected

POMK (HGNC:26267): (protein O-mannose kinase) This gene encodes a protein that may be involved in the presentation of the laminin-binding O-linked carbohydrate chain of alpha-dystroglycan (a-DG), which forms transmembrane linkages between the extracellular matrix and the exoskeleton. Some pathogens use this O-linked carbohydrate unit for host entry. Loss of function compound heterozygous mutations in this gene were found in a human patient affected by the Walker-Warburg syndrome (WWS) phenotype. Mice lacking this gene contain misplaced neurons (heterotopia) in some regions of the brain, possibly from defects in neuronal migration. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

POMK links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 11 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 8-43103585-G-GC is Pathogenic according to our data. Variant chr8-43103585-G-GC is described in ClinVar as [Likely_pathogenic]. Clinvar id is 817678.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
POMK	NM_032237.5 link	c.43dupC	p.Arg15ProfsTer85	frameshift_variant	Exon 4 of 5	ENST00000331373.10	NP_115613.1	Q9H5K3
POMK	NM_001277971.2 link	c.43dupC	p.Arg15ProfsTer85	frameshift_variant	Exon 3 of 4		NP_001264900.1	Q9H5K3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
POMK	ENST00000331373.10 link	c.43dupC	p.Arg15ProfsTer85	frameshift_variant	Exon 4 of 5	2	NM_032237.5	ENSP00000331258.5		Q9H5K3

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152062

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:

0.000386

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:

0.0000239

AC:

AN:

251106

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135744

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000441

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000123

AC:

AN:

1461864

Hom.:

Cov.:

AF XY:

0.0000110

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000153

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152180

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74396

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000386

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000868

Hom.:

Bravo

AF:

0.0000189

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:1

Jun 13, 2018

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.43dupC variant in the POMK gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The c.43dupC variant causes a frameshift starting with codon Arginine 15, changes this amino acid to a Proline residue, and creates a premature Stop codon at position 85 of the new reading frame, denoted p.Arg15ProfsX85. This variant is predicted to cause loss of normal protein function through protein truncation. The c.43dupC variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016). We interpret c.43dupC as a likely pathogenic variant. -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type a, 12;C4015184:Limb-girdle muscular dystrophy due to POMK deficiency

Pathogenic:1

Mar 18, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the POMK protein in which other variant(s) (p.Gln109*) have been determined to be pathogenic (PMID: 24556084, 24925318). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. ClinVar contains an entry for this variant (Variation ID: 817678). This variant has not been reported in the literature in individuals affected with POMK-related conditions. This variant is present in population databases (rs749980792, gnomAD 0.006%). This sequence change creates a premature translational stop signal (p.Arg15Profs*85) in the POMK gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 336 amino acid(s) of the POMK protein. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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

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