NM_024079.5:c.396dupA

Variant names:

• chr11-78121146-C-CT
• rs753631154
• NM_024079.5:c.396dupA

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_024079.5(ALG8):​c.396dupA​(p.Val133SerfsTer3) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,716 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: ALG8 NM_024079.5 frameshift
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 0.911
• Publications: 4 publications found

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]

ALG8 Gene-Disease associations (from GenCC):

• autosomal dominant polycystic kidney disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• ALG8-congenital disorder of glycosylation

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
• polycystic liver disease 3 with or without kidney cysts

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-78121146-C-CT is Pathogenic according to our data. Variant chr11-78121146-C-CT is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2559.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024079.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALG8	NM_024079.5	MANE Select	c.396dupA	p.Val133SerfsTer3	frameshift	Exon 4 of 13	NP_076984.2	A0A024R5K5
	ALG8	NM_001425224.1		c.396dupA	p.Val133SerfsTer3	frameshift	Exon 4 of 14	NP_001412153.1
	ALG8	NM_001425225.1		c.396dupA	p.Val133SerfsTer3	frameshift	Exon 4 of 14	NP_001412154.1	H0YDD3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALG8	ENST00000299626.10	TSL:1 MANE Select	c.396dupA	p.Val133SerfsTer3	frameshift	Exon 4 of 13	ENSP00000299626.5	Q9BVK2-1
	ALG8	ENST00000532050.5	TSL:1	n.396dupA		non_coding_transcript_exon	Exon 4 of 8	ENSP00000437199.1	E9PNE2
	ALG8	ENST00000679559.1		c.396dupA	p.Val133SerfsTer3	frameshift	Exon 4 of 14	ENSP00000505433.1	A0A7P0T919

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152124 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000656

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

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 250996 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000145

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: 0.00000274 AC: 4 AN: 1461474 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727062

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.0000894 AC: 4 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39660

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53204

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111892

Other (OTH) AF: 0.00 AC: 0 AN: 60380

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152242 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74440

African (AFR) AF: 0.00 AC: 0 AN: 41556

American (AMR) AF: 0.0000655 AC: 1 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5190

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68012

Other (OTH) AF: 0.00 AC: 0 AN: 2106

Alfa AF: 0.0000131 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	1	-	ALG8 congenital disorder of glycosylation (2)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.91
Mutation Taster		=6/194	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs753631154; hg19: chr11-77832192;