NM_002408.4:c.733G>C

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 1P and 5B. PP2BP4_StrongBS1_Supporting

The NM_002408.4(MGAT2):​c.733G>C​(p.Val245Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00153 in 1,614,190 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.00097 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0016 ( 0 hom. )

Consequence

MGAT2
NM_002408.4 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: 4.34

Publications

5 publications found
Variant links:
Genes affected
MGAT2 (HGNC:7045): (alpha-1,6-mannosyl-glycoprotein 2-beta-N-acetylglucosaminyltransferase) The product of this gene is a Golgi enzyme catalyzing an essential step in the conversion of oligomannose to complex N-glycans. The enzyme has the typical glycosyltransferase domains: a short N-terminal cytoplasmic domain, a hydrophobic non-cleavable signal-anchor domain, and a C-terminal catalytic domain. Mutations in this gene may lead to carbohydrate-deficient glycoprotein syndrome, type II. The coding region of this gene is intronless. Transcript variants with a spliced 5' UTR may exist, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]
MGAT2 Gene-Disease associations (from GenCC):
  • MGAT2-congenital disorder of glycosylation
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), PanelApp Australia, Orphanet, Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 6 curated pathogenic missense variants (we use a threshold of 10). The gene has 0 curated benign missense variants. Gene score misZ: 0.51522 (below the threshold of 3.09). Trascript score misZ: 0.84141 (below the threshold of 3.09). GenCC associations: The gene is linked to MGAT2-congenital disorder of glycosylation.
BP4
Computational evidence support a benign effect (MetaRNN=0.012908131).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000972 (148/152296) while in subpopulation NFE AF = 0.00171 (116/68024). AF 95% confidence interval is 0.00145. There are 0 homozygotes in GnomAd4. There are 71 alleles in the male GnomAd4 subpopulation. Median coverage is 33. 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
MGAT2NM_002408.4 linkc.733G>C p.Val245Leu missense_variant Exon 1 of 1 ENST00000305386.4 NP_002399.1 Q10469

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MGAT2ENST00000305386.4 linkc.733G>C p.Val245Leu missense_variant Exon 1 of 1 6 NM_002408.4 ENSP00000307423.2 Q10469
ENSG00000258377ENST00000555043.2 linkn.1480C>G non_coding_transcript_exon_variant Exon 1 of 2 2

Frequencies

GnomAD3 genomes
AF:
0.000973
AC:
148
AN:
152178
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000217
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000524
Gnomad ASJ
AF:
0.00202
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.000283
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00171
Gnomad OTH
AF:
0.00144
GnomAD2 exomes
AF:
0.00102
AC:
257
AN:
251470
AF XY:
0.00105
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.000347
Gnomad ASJ exome
AF:
0.00149
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000416
Gnomad NFE exome
AF:
0.00178
Gnomad OTH exome
AF:
0.00261
GnomAD4 exome
AF:
0.00159
AC:
2318
AN:
1461894
Hom.:
0
Cov.:
32
AF XY:
0.00149
AC XY:
1087
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.000179
AC:
6
AN:
33480
American (AMR)
AF:
0.000402
AC:
18
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00149
AC:
39
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.000174
AC:
15
AN:
86258
European-Finnish (FIN)
AF:
0.000262
AC:
14
AN:
53420
Middle Eastern (MID)
AF:
0.00312
AC:
18
AN:
5768
European-Non Finnish (NFE)
AF:
0.00187
AC:
2085
AN:
1112012
Other (OTH)
AF:
0.00204
AC:
123
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
153
306
460
613
766
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
70
140
210
280
350
<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:
0.000972
AC:
148
AN:
152296
Hom.:
0
Cov.:
33
AF XY:
0.000953
AC XY:
71
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.000217
AC:
9
AN:
41562
American (AMR)
AF:
0.000523
AC:
8
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00202
AC:
7
AN:
3468
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5186
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.000283
AC:
3
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00171
AC:
116
AN:
68024
Other (OTH)
AF:
0.00142
AC:
3
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
8
16
23
31
39
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:
0.00180
Hom.:
0
Bravo
AF:
0.00108
TwinsUK
AF:
0.00243
AC:
9
ALSPAC
AF:
0.00259
AC:
10
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00186
AC:
16
ExAC
AF:
0.00101
AC:
122
EpiCase
AF:
0.00251
EpiControl
AF:
0.00190

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:5
Mar 14, 2013
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 24, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported previously in published literature in an individual submitted for NGS panel testing for congenital disorders of glycosylation; no additional phenotypic or familial segregation details were provided (Jones et al., 2013); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Observed in 273/277240 (0.099%) alleles in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 23806237) -

Oct 09, 2015
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 17, 2019
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The MGAT2 p.Val245Leu variant was not identified in the literature nor was it identified in Cosmic. The variant was identified in dbSNP (ID: rs117536357), ClinVar (classified as a VUS by EGL Genetics Diagnostics and Center for Pediatric Genomic Medicine, Children's Mercy Hospital) and LOVD 3.0. The variant was also identified in control databases in 284 of 282872 chromosomes (1 homozygous) at a frequency of 0.001004 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Other in 16 of 7224 chromosomes (freq: 0.002215), European (non-Finnish) in 226 of 129192 chromosomes (freq: 0.001749), Ashkenazi Jewish in 15 of 10370 chromosomes (freq: 0.001446), European (Finnish) in 11 of 25116 chromosomes (freq: 0.000438), Latino in 12 of 35440 chromosomes (freq: 0.000339), African in 3 of 24960 chromosomes (freq: 0.00012) and South Asian in 1 of 30616 chromosomes (freq: 0.000033); it was not observed in the East Asian population. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. The p.Val245 residue is conserved in mammals but not in more distantly related organisms and four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein; this information is not predictive enough to rule out pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

MGAT2-congenital disorder of glycosylation Uncertain:3
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 06, 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 leucine, which is neutral and non-polar, at codon 245 of the MGAT2 protein (p.Val245Leu). This variant is present in population databases (rs117536357, gnomAD 0.2%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with clinical features of a congenital disorder of glycosylation (PMID: 23806237). ClinVar contains an entry for this variant (Variation ID: 94062). 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 tolerated. 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
Benign
0.33
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.22
CADD
Benign
20
DANN
Benign
0.88
DEOGEN2
Benign
0.35
T
Eigen
Benign
-0.37
Eigen_PC
Benign
-0.11
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Benign
0.84
T
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.013
T
MetaSVM
Benign
-0.81
T
MutationAssessor
Benign
0.63
N
PhyloP100
4.3
PrimateAI
Uncertain
0.54
T
PROVEAN
Benign
0.84
N
REVEL
Benign
0.23
Sift
Benign
1.0
T
Sift4G
Benign
1.0
T
Polyphen
0.0090
B
Vest4
0.15
MutPred
0.53
Loss of methylation at K246 (P = 0.0348);
MVP
0.41
MPC
0.39
ClinPred
0.053
T
GERP RS
5.1
Varity_R
0.20
gMVP
0.68
Mutation Taster
=89/11
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: rs117536357; hg19: chr14-50088719; API