chr9-131521374-T-C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001077365.2(POMT1):​c.1727T>C​(p.Val576Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00016 in 1,614,054 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.00024 ( 0 hom., cov: 32)
Exomes š‘“: 0.00015 ( 0 hom. )

Consequence

POMT1
NM_001077365.2 missense

Scores

1
5
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:1

Conservation

PhyloP100: 2.47

Publications

1 publications found
Variant links:
Genes affected
POMT1 (HGNC:9202): (protein O-mannosyltransferase 1) The protein encoded by this gene is an O-mannosyltransferase that requires interaction with the product of the POMT2 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) and limb-girdle muscular dystrophy type 2K (LGMD2K). Several transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2008]
POMT1 Gene-Disease associations (from GenCC):
  • muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Laboratory for Molecular Medicine, Genomics England PanelApp
  • myopathy caused by variation in POMT1
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B1
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • autosomal recessive limb-girdle muscular dystrophy type 2K
    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
  • congenital muscular dystrophy without 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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.217911).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POMT1NM_001077365.2 linkc.1727T>C p.Val576Ala missense_variant Exon 18 of 20 ENST00000402686.8 NP_001070833.1 Q9Y6A1-2A0A140VKE0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POMT1ENST00000402686.8 linkc.1727T>C p.Val576Ala missense_variant Exon 18 of 20 1 NM_001077365.2 ENSP00000385797.4 Q9Y6A1-2

Frequencies

GnomAD3 genomes
AF:
0.000243
AC:
37
AN:
152200
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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:
0.000426
Gnomad OTH
AF:
0.000956
GnomAD2 exomes
AF:
0.000103
AC:
26
AN:
251460
AF XY:
0.000103
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000202
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000152
AC:
222
AN:
1461854
Hom.:
0
Cov.:
31
AF XY:
0.000142
AC XY:
103
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33480
American (AMR)
AF:
0.000134
AC:
6
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000189
AC:
210
AN:
1111978
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
13
26
40
53
66
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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
AF:
0.000243
AC:
37
AN:
152200
Hom.:
0
Cov.:
32
AF XY:
0.000188
AC XY:
14
AN XY:
74362
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41446
American (AMR)
AF:
0.000196
AC:
3
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000426
AC:
29
AN:
68040
Other (OTH)
AF:
0.000956
AC:
2
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
4
7
11
14
18
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000212
Hom.:
0
Bravo
AF:
0.000193
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000988
AC:
12
EpiCase
AF:
0.000218
EpiControl
AF:
0.000296

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Nov 30, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 30564623, 22549409) -

Mar 23, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Autosomal recessive limb-girdle muscular dystrophy type 2K Uncertain:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Inborn genetic diseases Uncertain:1
Jun 29, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1793T>C (p.V598A) alteration is located in exon 18 (coding exon 17) of the POMT1 gene. This alteration results from a T to C substitution at nucleotide position 1793, causing the valine (V) at amino acid position 598 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Autosomal recessive limb-girdle muscular dystrophy type 2K;C4284790:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1;C5436962:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B1 Uncertain:1
Apr 07, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Walker-Warburg congenital muscular dystrophy;C1836373:Autosomal recessive limb-girdle muscular dystrophy type 2K;C5436962:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B1 Uncertain:1
Sep 13, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 598 of the POMT1 protein (p.Val598Ala). This variant is present in population databases (rs144338642, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with POMT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 260143). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt POMT1 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

not specified Benign:1
-
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.10
CADD
Benign
21
DANN
Benign
0.79
DEOGEN2
Pathogenic
0.86
.;.;.;D;.;D
Eigen
Benign
-0.29
Eigen_PC
Benign
-0.19
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.79
T;T;T;T;.;T
M_CAP
Uncertain
0.14
D
MetaRNN
Benign
0.22
T;T;T;T;T;T
MetaSVM
Uncertain
0.025
D
MutationAssessor
Benign
1.5
.;.;.;L;.;.
PhyloP100
2.5
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
-2.3
N;N;N;N;N;N
REVEL
Uncertain
0.31
Sift
Benign
0.21
T;T;T;T;T;T
Sift4G
Benign
0.17
T;T;T;T;T;D
Polyphen
0.0010, 0.0050
.;B;.;B;B;.
Vest4
0.32
MutPred
0.46
.;.;.;Loss of stability (P = 0.0469);.;.;
MVP
0.86
MPC
0.30
ClinPred
0.061
T
GERP RS
4.7
Varity_R
0.18
gMVP
0.53
Mutation Taster
=72/28
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

Publications

Other links and lift over

dbSNP: rs144338642; hg19: chr9-134396761; API