rs535544133

Variant summary

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

The NM_001077365.2(POMT1):​c.2059G>A​(p.Ala687Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000255 in 1,606,136 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. A687V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

POMT1
NM_001077365.2 missense

Scores

8
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 3.30

Publications

2 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=0.165786).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POMT1NM_001077365.2 linkc.2059G>A p.Ala687Thr missense_variant Exon 20 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.2059G>A p.Ala687Thr missense_variant Exon 20 of 20 1 NM_001077365.2 ENSP00000385797.4 Q9Y6A1-2

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152170
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000772
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.0000620
AC:
15
AN:
241978
AF XY:
0.0000534
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000177
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000274
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000273
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000206
AC:
30
AN:
1453848
Hom.:
0
Cov.:
34
AF XY:
0.0000277
AC XY:
20
AN XY:
722812
show subpopulations
African (AFR)
AF:
0.0000300
AC:
1
AN:
33354
American (AMR)
AF:
0.000159
AC:
7
AN:
44164
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25952
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39668
South Asian (SAS)
AF:
0.0000352
AC:
3
AN:
85236
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51288
Middle Eastern (MID)
AF:
0.000240
AC:
1
AN:
4162
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1109962
Other (OTH)
AF:
0.0000333
AC:
2
AN:
60062
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
2
4
5
7
9
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
AF:
0.0000722
AC:
11
AN:
152288
Hom.:
0
Cov.:
33
AF XY:
0.0000537
AC XY:
4
AN XY:
74460
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41544
American (AMR)
AF:
0.000131
AC:
2
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000773
AC:
4
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68028
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.548
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

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:
0.0000434
Hom.:
0
Bravo
AF:
0.0000907
ExAC
AF:
0.0000659
AC:
8
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 08, 2014
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Sep 27, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2125G>A (p.A709T) alteration is located in exon 20 (coding exon 19) of the POMT1 gene. This alteration results from a G to A substitution at nucleotide position 2125, causing the alanine (A) at amino acid position 709 to be replaced by a threonine (T). 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
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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
Oct 18, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 709 of the POMT1 protein (p.Ala709Thr). This variant is present in population databases (rs535544133, gnomAD 0.04%). 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: 211945). 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 provided Uncertain:1
Feb 14, 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: 22549409) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.16
T
BayesDel_noAF
Benign
-0.16
CADD
Benign
22
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.64
.;.;.;D;.;T
Eigen
Benign
-0.012
Eigen_PC
Benign
-0.031
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.83
T;T;T;T;.;T
M_CAP
Uncertain
0.12
D
MetaRNN
Benign
0.17
T;T;T;T;T;T
MetaSVM
Uncertain
-0.12
T
MutationAssessor
Uncertain
2.0
.;.;.;M;.;.
PhyloP100
3.3
PrimateAI
Benign
0.35
T
PROVEAN
Benign
-0.78
N;N;N;N;N;N
REVEL
Uncertain
0.31
Sift
Benign
0.031
D;D;D;D;D;T
Sift4G
Uncertain
0.022
D;D;D;D;D;T
Polyphen
0.94, 0.85
.;P;.;P;P;.
Vest4
0.28
MutPred
0.46
.;.;.;Gain of glycosylation at A709 (P = 0.0721);.;.;
MVP
0.91
MPC
0.33
ClinPred
0.065
T
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.20
gMVP
0.35
Mutation Taster
=93/7
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: rs535544133; hg19: chr9-134398374; API