Variant chr1-63415875-TTTG-T details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM4_SupportingPP5

The NM_013339.4(ALG6):c.908_910del(p.Cys303del) variant causes a inframe deletion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000125 in 1,600,196 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

ALG6
NM_013339.4 inframe_deletion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:2

Conservation

PhyloP100: 2.22

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:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM4

Nonframeshift variant in NON repetitive region in NM_013339.4. Strenght limited to Supporting due to length of the change: 1aa.

PP5

Variant 1-63415875-TTTG-T is Pathogenic according to our data. Variant chr1-63415875-TTTG-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 372732.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ALG6	NM_013339.4 linkuse as main transcript	c.908_910del	p.Cys303del	inframe_deletion	11/15	ENST00000263440.6	NP_037471.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ALG6	ENST00000263440.6 linkuse as main transcript	c.908_910del	p.Cys303del	inframe_deletion	11/15	5	NM_013339.4	ENSP00000263440	P1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152178

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.0000131

AC:

AN:

1448018

Hom.:

AF XY:

0.0000166

AC XY:

AN XY:

721146

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.0000164

Gnomad4 OTH exome

AF:

0.0000167

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152178

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74352

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not specified

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Mar 23, 2022	Variant summary: ALG6 c.908_910delGTT (p.Cys303del) results in an in-frame deletion that is predicted to remove one amino acid from the encoded protein. The variant was absent in 249388 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.908_910delGTT has been reported in the literature as a presumed compound heterozygous genotype in at-least one individual affected with alpha-1,3-glucosyltransferase congenital disorder of glycosylation (ALG6-CDG) (example, Morava_2016) and also listed without a second allele or zygosity specified in a mutational update report (example, Haeuptle_2009). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic and one laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Nov 16, 2015	- -

not provided

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Sep 23, 2016

The c.908_910delGTT variant in the ALG6 gene has been previously reported in an least one individual with CDG who had a second variant, c.257+5G>A, although the phase for these two variants is unknown (Morava et al., 2016). The c.908_910delGTT variant causes an in-frame deletion of one amino acid, Cysteine 303, denoted p.C303del. This amino acid deletion occurs at a position that is not conserved across species. However, the c.908_910delGTT was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. We interpret c.908_910delGTT as a likely pathogenic variant. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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