9-99217967-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_033087.4(ALG2):c.1218G>C(p.Gln406His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,614,098 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000048 ( 1 hom. )

Consequence

ALG2
NM_033087.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.02

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
ALG2	NM_033087.4 linkuse as main transcript	c.1218G>C	p.Gln406His	missense_variant	2/2	ENST00000476832.2
ALG2	XM_047423996.1 linkuse as main transcript	c.939G>C	p.Gln313His	missense_variant	2/2
ALG2	NR_024532.2 linkuse as main transcript	n.1425G>C		non_coding_transcript_exon_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ALG2	ENST00000476832.2 linkuse as main transcript	c.1218G>C	p.Gln406His	missense_variant	2/2	1	NM_033087.4	P1	Q9H553-1
ALG2	ENST00000319033.7 linkuse as main transcript	c.939G>C	p.Gln313His	missense_variant	2/2	1			Q9H553-2
ALG2	ENST00000238477.5 linkuse as main transcript	c.*960G>C		3_prime_UTR_variant, NMD_transcript_variant	3/3	2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000479

AC:

AN:

1461880

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74352

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000142

Hom.:

Bravo

AF:

0.0000529

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 12, 2021

The c.1218G>C (p.Q406H) alteration is located in exon 2 (coding exon 2) of the ALG2 gene. This alteration results from a G to C substitution at nucleotide position 1218, causing the glutamine (Q) at amino acid position 406 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

ALG2-congenital disorder of glycosylation;C4015597:Congenital myasthenic syndrome 14

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 13, 2022

This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 406 of the ALG2 protein (p.Gln406His). This variant is present in population databases (rs763754023, gnomAD 0.007%). 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: 1039238). 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: "Possibly Damaging"; Align-GVGD: "Class C0"). 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

0.26

BayesDel_addAF

Uncertain

0.050

BayesDel_noAF

Benign

-0.17

Cadd

Benign

Dann

Benign

0.97

DEOGEN2

Benign

0.19

T;.

Eigen

Benign

-0.0070

Eigen_PC

Benign

0.079

FATHMM_MKL

Uncertain

0.91

LIST_S2

Uncertain

0.87

D;D

M_CAP

Uncertain

0.16

MetaRNN

Uncertain

0.45

T;T

MetaSVM

Uncertain

-0.24

MutationAssessor

Uncertain

2.2

M;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Benign

0.48

PROVEAN

Uncertain

-2.4

N;N

REVEL

Uncertain

0.41

Sift

Benign

0.16

T;T

Sift4G

Benign

0.13

T;T

Polyphen

0.38

B;B

Vest4

0.58

MutPred

0.36

Loss of MoRF binding (P = 0.0965);.;

MVP

0.81

MPC

0.44

ClinPred

0.83

GERP RS

4.0

Varity_R

0.12

gMVP

0.71

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

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