NM_024105.4:c.652A>G

Variant summary

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

The NM_024105.4(ALG12):​c.652A>G​(p.Ile218Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000096 in 1,614,122 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00056 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000047 ( 0 hom. )

Consequence

ALG12
NM_024105.4 missense

Scores

18

Clinical Significance

Uncertain significance criteria provided, single submitter U:1B:1

Conservation

PhyloP100: -3.53

Publications

1 publications found
Variant links:
Genes affected
ALG12 (HGNC:19358): (ALG12 alpha-1,6-mannosyltransferase) This gene encodes a member of the glycosyltransferase 22 family. The encoded protein catalyzes the addition of the eighth mannose residue in an alpha-1,6 linkage onto the dolichol-PP-oligosaccharide precursor (dolichol-PP-Man(7)GlcNAc(2)) required for protein glycosylation. Mutations in this gene have been associated with congenital disorder of glycosylation type Ig (CDG-Ig)characterized by abnormal N-glycosylation. [provided by RefSeq, Jul 2008]
ALG12 Gene-Disease associations (from GenCC):
  • ALG12-congenital disorder of glycosylation
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, G2P, ClinGen, Labcorp Genetics (formerly Invitae), PanelApp Australia, 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=0.02099213).
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.000564 (86/152376) while in subpopulation AFR AF = 0.00202 (84/41582). AF 95% confidence interval is 0.00167. There are 0 homozygotes in GnomAd4. There are 40 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
ALG12NM_024105.4 linkc.652A>G p.Ile218Val missense_variant Exon 5 of 10 ENST00000330817.11 NP_077010.1
ALG12XM_017028936.2 linkc.652A>G p.Ile218Val missense_variant Exon 5 of 10 XP_016884425.1
ALG12XM_017028937.2 linkc.652A>G p.Ile218Val missense_variant Exon 5 of 11 XP_016884426.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALG12ENST00000330817.11 linkc.652A>G p.Ile218Val missense_variant Exon 5 of 10 1 NM_024105.4 ENSP00000333813.5
ALG12ENST00000492791.1 linkn.181A>G non_coding_transcript_exon_variant Exon 1 of 6 3 ENSP00000417387.1

Frequencies

GnomAD3 genomes
AF:
0.000565
AC:
86
AN:
152258
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00203
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.000478
GnomAD2 exomes
AF:
0.000123
AC:
31
AN:
251102
AF XY:
0.0000663
show subpopulations
Gnomad AFR exome
AF:
0.00179
Gnomad AMR exome
AF:
0.0000578
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:
0.0000472
AC:
69
AN:
1461746
Hom.:
0
Cov.:
34
AF XY:
0.0000454
AC XY:
33
AN XY:
727162
show subpopulations
African (AFR)
AF:
0.00179
AC:
60
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
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:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53316
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111976
Other (OTH)
AF:
0.000132
AC:
8
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
4
9
13
18
22
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:
0.000564
AC:
86
AN:
152376
Hom.:
0
Cov.:
33
AF XY:
0.000537
AC XY:
40
AN XY:
74526
show subpopulations
African (AFR)
AF:
0.00202
AC:
84
AN:
41582
American (AMR)
AF:
0.0000653
AC:
1
AN:
15312
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68040
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
5
10
15
20
25
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:
0.000260
Hom.:
1
Bravo
AF:
0.000676
ESP6500AA
AF:
0.00113
AC:
5
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000148
AC:
18
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

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

Submissions by phenotype

ALG12-congenital disorder of glycosylation Uncertain:1
Aug 23, 2022
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 valine, which is neutral and non-polar, at codon 218 of the ALG12 protein (p.Ile218Val). This variant is present in population databases (rs146322225, gnomAD 0.2%). This variant has not been reported in the literature in individuals affected with ALG12-related conditions. ClinVar contains an entry for this variant (Variation ID: 578572). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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.

ALG12-related disorder Benign:1
Mar 28, 2024
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications).

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.081
BayesDel_addAF
Benign
-0.55
T
BayesDel_noAF
Benign
-0.57
CADD
Benign
0.0010
DANN
Benign
0.23
DEOGEN2
Benign
0.037
T
Eigen
Benign
-2.1
Eigen_PC
Benign
-2.2
FATHMM_MKL
Benign
0.014
N
LIST_S2
Benign
0.70
T
M_CAP
Benign
0.011
T
MetaRNN
Benign
0.021
T
MetaSVM
Benign
-0.99
T
MutationAssessor
Benign
0.43
N
PhyloP100
-3.5
PrimateAI
Benign
0.26
T
PROVEAN
Benign
-0.080
N
REVEL
Benign
0.030
Sift
Benign
1.0
T
Sift4G
Benign
1.0
T
Vest4
0.069
ClinPred
0.012
T
GERP RS
-8.9
Varity_R
0.035
gMVP
0.35
Mutation Taster
=97/3
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: rs146322225; hg19: chr22-50303554; API