1-63411333-T-G

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_013339.4(ALG6):​c.680+2T>G variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000124 in 1,612,972 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

ALG6
NM_013339.4 splice_donor, intron

Scores

5
1
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 5.68
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.12139107 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 1-63411333-T-G is Pathogenic according to our data. Variant chr1-63411333-T-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 30421.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-63411333-T-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
ALG6NM_013339.4 linkuse as main transcriptc.680+2T>G splice_donor_variant, intron_variant ENST00000263440.6 NP_037471.2 Q9Y672

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
ALG6ENST00000263440.6 linkuse as main transcriptc.680+2T>G splice_donor_variant, intron_variant 5 NM_013339.4 ENSP00000263440.5 Q9Y672

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
32
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
GnomAD3 exomes
AF:
0.00000802
AC:
2
AN:
249296
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
134996
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000997
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460844
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
726670
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.0000383
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74324
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:
0.0000113

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

ALG6-congenital disorder of glycosylation 1C Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsAug 02, 2023- -
Likely pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Nov 16, 2021NM_013339.3(ALG6):c.680+2T>G is a canonical splice variant classified as likely pathogenic in the context of congenital disorder of glycosylation type Ic. c.680+2T>G has been observed in cases with relevant disease (PMID: 16007612, 27287710). Functional assessments of this variant are not available in the literature. c.680+2T>G has been observed in population frequency databases (gnomAD: OTH 0.02%). NM_013339.3(ALG6):c.680+2T>G is a canonical splice variant that has been observed more frequently in cases with the relevant disease than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -
Pathogenic, no assertion criteria providedliterature onlyOMIMAug 15, 2005- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 16, 2023This variant is also known as IVS7+2T>G. This sequence change affects a donor splice site in intron 8 of the ALG6 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in ALG6 are known to be pathogenic (PMID: 19862844). This variant is present in population databases (no rsID available, gnomAD 0.01%). Disruption of this splice site has been observed in individual(s) with congenital disorder of glycosylation (PMID: 16007612). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 30421). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.38
CADD
Pathogenic
31
DANN
Uncertain
1.0
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.99
FATHMM_MKL
Pathogenic
0.99
D
GERP RS
5.5

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
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.

Other links and lift over

dbSNP: rs868768232; hg19: chr1-63877004; API