14-77320453-C-T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBS1_Supporting

The NM_013382.7(POMT2):​c.229G>A​(p.Asp77Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000105 in 1,546,402 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. D77D) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00045 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000067 ( 0 hom. )

Consequence

POMT2
NM_013382.7 missense

Scores

3
16

Clinical Significance

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

Conservation

PhyloP100: 0.663

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: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.024628252).
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000453 (69/152332) while in subpopulation AFR AF = 0.00156 (65/41576). AF 95% confidence interval is 0.00126. There are 0 homozygotes in GnomAd4. There are 37 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POMT2NM_013382.7 linkc.229G>A p.Asp77Asn missense_variant Exon 1 of 21 ENST00000261534.9 NP_037514.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POMT2ENST00000261534.9 linkc.229G>A p.Asp77Asn missense_variant Exon 1 of 21 1 NM_013382.7 ENSP00000261534.4

Frequencies

GnomAD3 genomes
AF:
0.000453
AC:
69
AN:
152214
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00157
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000130
AC:
19
AN:
146360
AF XY:
0.000102
show subpopulations
Gnomad AFR exome
AF:
0.000973
Gnomad AMR exome
AF:
0.000404
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000181
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000667
AC:
93
AN:
1394070
Hom.:
0
Cov.:
30
AF XY:
0.0000552
AC XY:
38
AN XY:
687916
show subpopulations
African (AFR)
AF:
0.00180
AC:
57
AN:
31624
American (AMR)
AF:
0.000504
AC:
18
AN:
35740
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25176
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35764
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79288
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
43918
Middle Eastern (MID)
AF:
0.000176
AC:
1
AN:
5698
European-Non Finnish (NFE)
AF:
0.00000649
AC:
7
AN:
1078912
Other (OTH)
AF:
0.000173
AC:
10
AN:
57950
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
6
13
19
26
32
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.000453
AC:
69
AN:
152332
Hom.:
0
Cov.:
32
AF XY:
0.000497
AC XY:
37
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.00156
AC:
65
AN:
41576
American (AMR)
AF:
0.000131
AC:
2
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
Heterozygous variant carriers
0
4
8
11
15
19
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:
0.000271
Hom.:
0
Bravo
AF:
0.000680
ESP6500AA
AF:
0.00145
AC:
6
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000642
AC:
6

ClinVar

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

Submissions by phenotype

not provided Uncertain:4
May 02, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 03, 2017
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 01, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis suggests 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, 17923109) -

Jun 20, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Jan 02, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.229G>A (p.D77N) alteration is located in exon 1 (coding exon 1) of the POMT2 gene. This alteration results from a G to A substitution at nucleotide position 229, causing the aspartic acid (D) at amino acid position 77 to be replaced by an asparagine (N). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

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;C4284790:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1 Uncertain:1
May 17, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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 Benign:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
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
0.077
BayesDel_addAF
Benign
-0.42
T
BayesDel_noAF
Benign
-0.41
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Benign
0.18
T
Eigen
Benign
-0.42
Eigen_PC
Benign
-0.28
FATHMM_MKL
Benign
0.43
N
LIST_S2
Uncertain
0.90
D
M_CAP
Uncertain
0.12
D
MetaRNN
Benign
0.025
T
MetaSVM
Benign
-0.89
T
MutationAssessor
Benign
1.0
L
PhyloP100
0.66
PrimateAI
Benign
0.37
T
PROVEAN
Benign
0.020
N
REVEL
Benign
0.25
Sift
Benign
0.49
T
Sift4G
Benign
0.48
T
Polyphen
0.0040
B
Vest4
0.35
MVP
0.85
MPC
0.082
ClinPred
0.023
T
GERP RS
4.3
PromoterAI
-0.025
Neutral
Varity_R
0.079
gMVP
0.51
Mutation Taster
=94/6
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: rs200992827; hg19: chr14-77786796; API