NM_033087.4:c.368T>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_033087.4(ALG2):​c.368T>C​(p.Val123Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000872 in 1,605,242 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V123M) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

ALG2
NM_033087.4 missense

Scores

4
12
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.95

Publications

0 publications found
Variant links:
Genes affected
ALG2 (HGNC:23159): (ALG2 alpha-1,3/1,6-mannosyltransferase) This gene encodes a member of the glycosyltransferase 1 family. The encoded protein acts as an alpha 1,3 mannosyltransferase, mannosylating Man(2)GlcNAc(2)-dolichol diphosphate and Man(1)GlcNAc(2)-dolichol diphosphate to form Man(3)GlcNAc(2)-dolichol diphosphate. Defects in this gene have been associated with congenital disorder of glycosylation type Ih (CDG-Ii). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2008]
ALG2 Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 14
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • ALG2-congenital disorder of glycosylation
    Inheritance: Unknown, AR Classification: STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P, PanelApp Australia, Orphanet, Ambry Genetics
  • congenital myasthenic syndromes with glycosylation defect
    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 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALG2NM_033087.4 linkc.368T>C p.Val123Ala missense_variant Exon 2 of 2 ENST00000476832.2 NP_149078.1
ALG2XM_047423996.1 linkc.89T>C p.Val30Ala missense_variant Exon 2 of 2 XP_047279952.1
ALG2NR_024532.2 linkn.575T>C non_coding_transcript_exon_variant Exon 3 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALG2ENST00000476832.2 linkc.368T>C p.Val123Ala missense_variant Exon 2 of 2 1 NM_033087.4 ENSP00000417764.1
ALG2ENST00000319033.7 linkc.89T>C p.Val30Ala missense_variant Exon 2 of 2 1 ENSP00000326609.6
ALG2ENST00000238477.5 linkn.*110T>C non_coding_transcript_exon_variant Exon 3 of 3 2 ENSP00000432675.2
ALG2ENST00000238477.5 linkn.*110T>C 3_prime_UTR_variant Exon 3 of 3 2 ENSP00000432675.2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152214
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000205
AC:
5
AN:
243430
AF XY:
0.0000151
show subpopulations
Gnomad AFR exome
AF:
0.000188
Gnomad AMR exome
AF:
0.0000580
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000482
AC:
7
AN:
1453028
Hom.:
0
Cov.:
31
AF XY:
0.00000415
AC XY:
3
AN XY:
723112
show subpopulations
African (AFR)
AF:
0.000119
AC:
4
AN:
33474
American (AMR)
AF:
0.0000447
AC:
2
AN:
44722
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:
44690
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111946
Other (OTH)
AF:
0.00
AC:
0
AN:
60338
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.489
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000460
AC:
7
AN:
152214
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.000169
AC:
7
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.532
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

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:
0.0000717
Hom.:
0
Bravo
AF:
0.0000491
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

ALG2-congenital disorder of glycosylation;C4015597:Congenital myasthenic syndrome 14 Uncertain:1
Aug 24, 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 alanine, which is neutral and non-polar, at codon 123 of the ALG2 protein (p.Val123Ala). This variant is present in population databases (rs762560638, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with ALG2-related conditions. ClinVar contains an entry for this variant (Variation ID: 575672). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C15"). 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
Uncertain
0.37
BayesDel_addAF
Benign
-0.12
T
BayesDel_noAF
Benign
-0.11
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.54
D;.
Eigen
Pathogenic
0.72
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.89
D;D
M_CAP
Uncertain
0.14
D
MetaRNN
Uncertain
0.65
D;D
MetaSVM
Uncertain
0.26
D
MutationAssessor
Uncertain
2.8
M;.
PhyloP100
8.9
PrimateAI
Uncertain
0.55
T
PROVEAN
Uncertain
-2.9
D;D
REVEL
Pathogenic
0.65
Sift
Uncertain
0.0040
D;D
Sift4G
Uncertain
0.0080
D;D
Polyphen
0.87
P;P
Vest4
0.46
MutPred
0.63
Gain of catalytic residue at V123 (P = 0.0247);.;
MVP
0.89
MPC
0.35
ClinPred
0.28
T
GERP RS
5.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.46
gMVP
0.88
Mutation Taster
=63/37
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: rs762560638; hg19: chr9-101981099; API