14-77296250-T-G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_013382.7(POMT2):​c.1030A>C​(p.Thr344Pro) variant causes a missense change. The variant allele was found at a frequency of 0.000000688 in 1,453,954 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T344S) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

POMT2
NM_013382.7 missense

Scores

12
6
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.20

Publications

1 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: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.905

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POMT2NM_013382.7 linkc.1030A>C p.Thr344Pro missense_variant Exon 9 of 21 ENST00000261534.9 NP_037514.2 Q9UKY4-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POMT2ENST00000261534.9 linkc.1030A>C p.Thr344Pro missense_variant Exon 9 of 21 1 NM_013382.7 ENSP00000261534.4 Q9UKY4-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.88e-7
AC:
1
AN:
1453954
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
722224
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33430
American (AMR)
AF:
0.00
AC:
0
AN:
43688
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25858
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39492
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84208
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52484
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5758
European-Non Finnish (NFE)
AF:
9.02e-7
AC:
1
AN:
1108880
Other (OTH)
AF:
0.00
AC:
0
AN:
60156
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
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 Uncertain:1
Sep 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant disrupts the p.Thr344 amino acid residue in POMT2. Other variant(s) that disrupt this residue have been observed in individuals with POMT2-related conditions (PMID: 29175898), which suggests that this may be a clinically significant amino acid residue. This sequence change replaces threonine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 344 of the POMT2 protein (p.Thr344Pro). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with limb-girdle muscular dystrophy and/or POMT2-related conditions (PMID: 29175898, 32528171). ClinVar contains an entry for this variant (Variation ID: 538736). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.44
D
BayesDel_noAF
Pathogenic
0.39
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.77
D
Eigen
Pathogenic
0.80
Eigen_PC
Pathogenic
0.69
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.95
D
M_CAP
Pathogenic
0.39
D
MetaRNN
Pathogenic
0.90
D
MetaSVM
Pathogenic
0.92
D
MutationAssessor
Pathogenic
4.4
H
PhyloP100
6.2
PrimateAI
Uncertain
0.66
T
PROVEAN
Pathogenic
-5.4
D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.0050
D
Polyphen
1.0
D
Vest4
0.89
MutPred
0.61
Gain of catalytic residue at Y339 (P = 2e-04);
MVP
0.96
MPC
0.52
ClinPred
1.0
D
GERP RS
5.0
Varity_R
0.91
gMVP
0.89
Mutation Taster
=20/80
disease causing

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: rs1285454398; hg19: chr14-77762593; API