NM_024079.5:c.1540G>A

Variant names:

• chr11-78101005-C-T
• NM_024079.5:c.1540G>A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_024079.5(ALG8):​c.1540G>A​(p.Val514Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,884 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ALG8 NM_024079.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.32

Genes affected

ALG8 (HGNC:23161): (ALG8 alpha-1,3-glucosyltransferase) This gene encodes a member of the ALG6/ALG8 glucosyltransferase family. The encoded protein catalyzes the addition of the second glucose residue to the lipid-linked oligosaccharide precursor for N-linked glycosylation of proteins. Mutations in this gene have been associated with congenital disorder of glycosylation type Ih (CDG-Ih). Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12587503).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ALG8	NM_024079.5	c.1540G>A	p.Val514Ile	missense_variant	Exon 13 of 13	ENST00000299626.10	NP_076984.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ALG8	ENST00000299626.10	c.1540G>A	p.Val514Ile	missense_variant	Exon 13 of 13	1	NM_024079.5	ENSP00000299626.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461884 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

ALG8 congenital disorder of glycosylation Uncertain:1

Dec 05, 2023

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 isoleucine, which is neutral and non-polar, at codon 514 of the ALG8 protein (p.Val514Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ALG8-related conditions. 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 not expected to disrupt ALG8 protein function with a negative predictive value of 80%. 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	0.079
BayesDel_addAF	Benign	-0.081	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	18
DANN	Benign	0.95
DEOGEN2	Benign	0.043	T;.
Eigen	Benign	-0.27
Eigen_PC	Benign	-0.12
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Benign	0.69	T;T
M_CAP	Benign	0.018	T
MetaRNN	Benign	0.13	T;T
MetaSVM	Benign	-0.81	T
MutationAssessor	Benign	1.1	L;.
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-0.080	N;N
REVEL	Benign	0.057
Sift	Benign	0.36	T;T
Sift4G	Benign	0.45	T;T
Polyphen		0.0030	B;.
Vest4		0.092
MutPred		0.49		Gain of helix (P = 0.132);.;
MVP		0.45
MPC		0.14
ClinPred		0.20	T
GERP RS		4.0
Varity_R		0.039
gMVP		0.19

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr11-77812051;