rs372079206

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PP3_StrongPP5

The NM_013339.4(ALG6):c.680G>A(p.Gly227Glu) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,612,960 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

ALG6
NM_013339.4 missense, splice_region

Scores

Splicing: ADA: 1.000

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:1

Conservation

PhyloP100: 9.35

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]

ALG6 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

PP5

Variant 1-63411331-G-A is Pathogenic according to our data. Variant chr1-63411331-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 381535.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=1, Pathogenic=3}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ALG6	NM_013339.4 link	c.680G>A	p.Gly227Glu	missense_variant, splice_region_variant	Exon 8 of 15	ENST00000263440.6	NP_037471.2	Q9Y672

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ALG6	ENST00000263440.6 link	c.680G>A	p.Gly227Glu	missense_variant, splice_region_variant	Exon 8 of 15	5	NM_013339.4	ENSP00000263440.5		Q9Y672

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152090

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

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

GnomAD3 exomes

AF:

0.0000240

AC:

AN:

249578

Hom.:

AF XY:

0.00000740

AC XY:

AN XY:

135094

show subpopulations

Gnomad AFR exome

AF:

0.000126

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000354

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000123

AC:

AN:

1460870

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

726686

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000153

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152090

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74302

show subpopulations

Gnomad4 AFR

AF:

0.0000242

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000708

Hom.:

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000412

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:5Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

ALG6-congenital disorder of glycosylation 1C

Pathogenic:4Uncertain:1

Nov 25, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 227 of the ALG6 protein (p.Gly227Glu). This variant also falls at the last nucleotide of exon 8, which is part of the consensus splice site for this exon. This variant is present in population databases (rs372079206, gnomAD 0.01%). This missense change has been observed in individual(s) with ALG6-related congenital disorder of glycosylation (PMID: 23430515, 27287710). ClinVar contains an entry for this variant (Variation ID: 381535). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt ALG6 protein function with a positive predictive value of 95%. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). For these reasons, this variant has been classified as Pathogenic. -

Nov 28, 2020

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Aug 28, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: ALG6 c.680G>A (p.Gly227Glu) results in a non-conservative amino acid change in the encoded protein sequence. Three of four in-silico tools predict a damaging effect of the variant on protein function. Several computational tools predict a significant impact on normal splicing: Three predict the variant weakens the canonical 5' donor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 2.4e-05 in 249578 control chromosomes (gnomAD). c.680G>A has been reported in the literature in multiple individuals affected with ALG6-related congenital disorder of glycosylation (examples: Schollen_2002, Dercksen_2012, Morava_2016, Clark_2023). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 36756224, 23430515, 27287710, 12357336). Four submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as VUS (n=1) and pathogenic/likely pathogenic (n=3). Based on the evidence outlined above, the variant was classified as pathogenic. -

Nov 08, 2021

Myriad Genetics, Inc.

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

NM_013339.3(ALG6):c.680G>A(G227E) is a missense variant classified as a variant of uncertain significance in the context of congenital disorder of glycosylation type Ic. G227E has been observed in cases with relevant disease (PMID: 27287710). Functional assessments of this variant are not available in the literature. G227E has been observed in population frequency databases (gnomAD: AFR 0.007%). In summary, there is insufficient evidence to classify NM_013339.3(ALG6):c.680G>A(G227E) as pathogenic or benign. Please note: this variant was assessed in the context of healthy population screening. -

Jun 10, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Pathogenic:1

Nov 05, 2024

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 12357336, 23430515, 27287710, 36756224) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.58

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.36

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.50

T;T

Eigen

Pathogenic

0.77

Eigen_PC

Pathogenic

0.77

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.92

.;D

M_CAP

Benign

0.070

MetaRNN

Pathogenic

0.86

D;D

MetaSVM

Uncertain

0.10

MutationAssessor

Uncertain

2.7

M;M

PrimateAI

Uncertain

0.68

PROVEAN

Benign

-2.3

N;N

REVEL

Pathogenic

0.76

Sift

Benign

0.16

T;T

Sift4G

Benign

0.30

T;.

Vest4

0.84

MVP

0.93

MPC

1.1

ClinPred

0.48

GERP RS

5.5

Varity_R

0.88

gMVP

0.77

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.97

SpliceAI score (max)

0.010

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over