rs200863680

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3PP5

The NM_017739.4(POMGNT1):​c.860T>G​(p.Ile287Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000681 in 1,614,108 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. I287I) has been classified as Likely benign.

Frequency

Genomes: š‘“ 0.000026 ( 0 hom., cov: 33)
Exomes š‘“: 0.0000048 ( 0 hom. )

Consequence

POMGNT1
NM_017739.4 missense

Scores

6
12
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:3

Conservation

PhyloP100: 8.90

Publications

1 publications found
Variant links:
Genes affected
POMGNT1 (HGNC:19139): (protein O-linked mannose N-acetylglucosaminyltransferase 1 (beta 1,2-)) This gene encodes a type II transmembrane protein that resides in the Golgi apparatus. It participates in O-mannosyl glycosylation and is specific for alpha linked terminal mannose. Mutations in this gene may be associated with muscle-eye-brain disease and several congenital muscular dystrophies. Alternatively spliced transcript variants that encode different protein isoforms have been described. [provided by RefSeq, Feb 2014]
TSPAN1 (HGNC:20657): (tetraspanin 1) The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.793
PP5
Variant 1-46194293-A-C is Pathogenic according to our data. Variant chr1-46194293-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 254270.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POMGNT1NM_017739.4 linkc.860T>G p.Ile287Ser missense_variant Exon 9 of 22 ENST00000371984.8 NP_060209.4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POMGNT1ENST00000371984.8 linkc.860T>G p.Ile287Ser missense_variant Exon 9 of 22 1 NM_017739.4 ENSP00000361052.3

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152102
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.0000119
AC:
3
AN:
251462
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461888
Hom.:
0
Cov.:
35
AF XY:
0.00000688
AC XY:
5
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
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:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000629
AC:
7
AN:
1112008
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000263
AC:
4
AN:
152220
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74436
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41530
American (AMR)
AF:
0.0000654
AC:
1
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67994
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
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

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:
0.00
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Retinitis pigmentosa 76 Pathogenic:1
Sep 20, 2016
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A3 Pathogenic:1
Mar 01, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Nov 15, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: POMGNT1 c.860T>G (p.Ile287Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251462 control chromosomes (gnomAD). c.860T>G has been reported in the literature in the compound heterozygous state in trans with a pathogenic variant in two siblings affected with autosomal recessive retinitis pigmentosa, without additional clinical features suggestive of muscular dystrophy, and it segregated with this phenotype in the family (Xu_2016). This report does not provide unequivocal conclusions about association of the variant with Limb-Girdle Muscular Dystrophy. At least one publication reports experimental evidence evaluating an impact on protein function (Xu_2016). The most pronounced variant effect results in 10%-<30% of WT enzyme activity. The following publications have been ascertained in the context of this evaluation (PMID: 36819107, 26908613). Three submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B3;C3150417:Autosomal recessive limb-girdle muscular dystrophy type 2O Uncertain:1
Aug 01, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 287 of the POMGNT1 protein (p.Ile287Ser). This variant is present in population databases (rs200863680, gnomAD 0.007%). This missense change has been observed in individual(s) with retinitis pigmentosa (PMID: 26908613). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 254270). 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 POMGNT1 protein function with a negative predictive value of 95%. 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
Aug 13, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.77
D;.
Eigen
Uncertain
0.67
Eigen_PC
Pathogenic
0.68
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.97
D;D
M_CAP
Uncertain
0.22
D
MetaRNN
Pathogenic
0.79
D;D
MetaSVM
Uncertain
0.30
D
MutationAssessor
Uncertain
2.2
M;M
PhyloP100
8.9
PrimateAI
Uncertain
0.52
T
PROVEAN
Uncertain
-4.2
D;D
REVEL
Pathogenic
0.65
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.0020
D;D
Polyphen
0.98
D;.
Vest4
0.82
MVP
0.97
MPC
0.99
ClinPred
0.95
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.77
gMVP
0.91
Mutation Taster
=7/93
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: rs200863680; hg19: chr1-46659965; API