rs768372697

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 7P and 1B. PM5PP3_StrongPP5BS1_Supporting

The NM_013339.4(ALG6):​c.338G>A​(p.Arg113His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000527 in 1,613,080 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R113C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

ALG6
NM_013339.4 missense

Scores

16
2
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:3

Conservation

PhyloP100: 9.14

Publications

3 publications found
Variant links:
Genes affected
ALG6 (HGNC:23157): (ALG6 alpha-1,3-glucosyltransferase) This gene encodes a member of the ALG6/ALG8 glucosyltransferase family. The encoded protein catalyzes the addition of the first glucose residue to the growing lipid-linked oligosaccharide precursor of N-linked glycosylation. Mutations in this gene are associated with congenital disorders of glycosylation type Ic. [provided by RefSeq, Jul 2008]
ITGB3BP (HGNC:6157): (integrin subunit beta 3 binding protein) This gene encodes a transcriptional coregulator that binds to and enhances the activity of members of the nuclear receptor families, thyroid hormone receptors and retinoid X receptors. This protein also acts as a corepressor of NF-kappaB-dependent signaling. This protein induces apoptosis in breast cancer cells through a caspase 2-mediated signaling pathway. This protein is also a component of the centromere-specific histone H3 variant nucleosome associated complex (CENP-NAC) and may be involved in mitotic progression by recruiting the histone H3 variant CENP-A to the centromere. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Sep 2011]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-63404532-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1066153.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.976
PP5
Variant 1-63404533-G-A is Pathogenic according to our data. Variant chr1-63404533-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 551854.
BS1
Variant frequency is greater than expected in population eas. GnomAdExome4 allele frequency = 0.0000507 (74/1460950) while in subpopulation EAS AF = 0.00159 (63/39606). AF 95% confidence interval is 0.00128. There are 0 homozygotes in GnomAdExome4. There are 36 alleles in the male GnomAdExome4 subpopulation. Median coverage is 30. 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
ALG6NM_013339.4 linkc.338G>A p.Arg113His missense_variant Exon 5 of 15 ENST00000263440.6 NP_037471.2 Q9Y672

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALG6ENST00000263440.6 linkc.338G>A p.Arg113His missense_variant Exon 5 of 15 5 NM_013339.4 ENSP00000263440.5 Q9Y672

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152130
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00115
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:
0.0000199
AC:
5
AN:
250898
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000218
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000507
AC:
74
AN:
1460950
Hom.:
0
Cov.:
30
AF XY:
0.0000495
AC XY:
36
AN XY:
726836
show subpopulations
African (AFR)
AF:
0.0000897
AC:
3
AN:
33446
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26116
East Asian (EAS)
AF:
0.00159
AC:
63
AN:
39606
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86240
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111288
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60356
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
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:
0.0000723
AC:
11
AN:
152130
Hom.:
0
Cov.:
32
AF XY:
0.000121
AC XY:
9
AN XY:
74304
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41442
American (AMR)
AF:
0.0000655
AC:
1
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00115
AC:
6
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68002
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
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:
0.0000667
Hom.:
2
Bravo
AF:
0.0000264
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

ALG6-congenital disorder of glycosylation 1C Pathogenic:5Uncertain:1
Apr 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 113 of the ALG6 protein (p.Arg113His). This variant is present in population databases (rs768372697, gnomAD 0.02%). This missense change has been observed in individual(s) with congenital disorder of glycosylation type 1c (PMID: 16321363). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 551854). 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 expected to disrupt ALG6 protein function with a positive predictive value of 80%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on ALG6 function (PMID: 16321363). This variant disrupts the p.Arg113 amino acid residue in ALG6. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 31117816). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Sep 29, 2023
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Mar 28, 2024
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 09, 2017
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

-
Juno Genomics, Hangzhou Juno Genomics, Inc
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM2_Supporting+PM5_Supporting+PP3_Strong+PM3 -

Mar 21, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jun 05, 2025
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: ALG6 c.338G>A (p.Arg113His) results in a non-conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 2e-05 in 250898 control chromosomes (gnomAD). c.338G>A has been observed in at least one compound heterozygous individual affected with Congenital Disorder Of Glycosylation Type 1C (Eklund_2006). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. However, a different missense affecting the same amino acid has been reported in affected individuals (PMIDs: 31117816, 39141102), suggesting a critical role for this residue. The following publications have been ascertained in the context of this evaluation (PMID: 27287710, 16321363). ClinVar contains an entry for this variant (Variation ID: 551854). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Inborn genetic diseases Uncertain:1
Apr 28, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.338G>A (p.R113H) alteration is located in exon 5 (coding exon 4) of the ALG6 gene. This alteration results from a G to A substitution at nucleotide position 338, causing the arginine (R) at amino acid position 113 to be replaced by a histidine (H). Based on data from gnomAD, this allele has an overall frequency of 0.002% (6/282284) total alleles studied. The highest observed frequency was 0.025% (5/19946) of East Asian alleles. This variant was reported in an individual with features consistent with autosomal recessive ALG6-related congenital disorder of glycosylation type I; however, many of these features could be accounted for by the 1p31.3p32.3del encompassing NFIA, and the relevance of this finding for ALG6 is unclear (Eklund, 2006). Other variant(s) at the same codon, c.337C>T (p.R113C), have been identified in individual(s) with features consistent with ALG6-related congenital disorder of glycosylation type I (van den Boogert, 2019). This amino acid position is highly conserved in available vertebrate species. This alteration is predicted to be deleterious by in silico analysis. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.90
BayesDel_addAF
Pathogenic
0.33
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.89
D;D
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.92
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
.;D
M_CAP
Uncertain
0.15
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.0
H;H
PhyloP100
9.1
PrimateAI
Uncertain
0.58
T
PROVEAN
Pathogenic
-4.9
D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Vest4
0.98
MVP
0.99
MPC
1.1
ClinPred
0.99
D
GERP RS
5.3
Varity_R
0.93
gMVP
0.92
Mutation Taster
=3/97
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
Splicevardb
2.0
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: rs768372697; hg19: chr1-63870204; COSMIC: COSV54763197; COSMIC: COSV54763197; API