rs72555372

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000404.4(GLB1):​c.1051C>T​(p.Arg351Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000116 in 1,460,972 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

GLB1
NM_000404.4 stop_gained

Scores

2
3
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 1.99
Variant links:
Genes affected
GLB1 (HGNC:4298): (galactosidase beta 1) This gene encodes a member of the glycosyl hydrolase 35 family of proteins. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate the mature lysosomal enzyme. This enzyme catalyzes the hydrolysis of a terminal beta-linked galactose residue from ganglioside substrates and other glycoconjugates. Mutations in this gene may result in GM1-gangliosidosis and Morquio B syndrome. [provided by RefSeq, Nov 2015]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 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 3-33046137-G-A is Pathogenic according to our data. Variant chr3-33046137-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 941.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GLB1NM_000404.4 linkuse as main transcriptc.1051C>T p.Arg351Ter stop_gained 10/16 ENST00000307363.10 NP_000395.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GLB1ENST00000307363.10 linkuse as main transcriptc.1051C>T p.Arg351Ter stop_gained 10/161 NM_000404.4 ENSP00000306920 P2

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD3 exomes
AF:
0.0000120
AC:
3
AN:
249506
Hom.:
0
AF XY:
0.0000148
AC XY:
2
AN XY:
135358
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000116
AC:
17
AN:
1460972
Hom.:
0
Cov.:
31
AF XY:
0.0000110
AC XY:
8
AN XY:
726834
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:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000117
Gnomad4 OTH exome
AF:
0.0000332
GnomAD4 genome
Cov.:
31
Alfa
AF:
0.0000401
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-IV-B Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpNov 16, 2017Variant summary: The GLB1 c.1051C>T (p.Arg351X) variant results in a premature termination codon, predicted to cause a truncated or absent GLB1 protein due to nonsense mediated decay, which are commonly known mechanisms for disease. This variant was found in 3/246162 control chromosomes at a frequency of 0.0000122, which does not exceed the estimated maximal expected allele frequency of a pathogenic GLB1 variant (0.0020412). The c.1051C>T has been reported in at least four affected, with residual GLB1 activity in their fibroblasts being less than 2% of normal via publications. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingGenomic Research Center, Shahid Beheshti University of Medical SciencesMay 03, 2020- -
Spastic ataxia Pathogenic:1
Pathogenic, criteria provided, single submitterresearchMolecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella MarisJan 04, 2021- -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGeneDxOct 23, 2024Identified in unrelated individuals with GM1-gangliosidosis in the published literature who were homozygous for this variant or harbored a second variant in GLB1 (PMID: 10841810, 15714521, 33240792); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at a significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 21497194, 8922281, 25600812, 31367523, 25525159, 33737400, 15714521, 22784478, 34445196, 33859490, 33240792, 10841810) -
GM1-gangliosidosis, type I, with cardiac involvement Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMMay 14, 2019- -
Mucopolysaccharidosis, MPS-IV-B;C0268271:Infantile GM1 gangliosidosis;C0268272:GM1 gangliosidosis type 2;C0268273:GM1 gangliosidosis type 3 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingCounsylFeb 14, 2017- -
GM1 gangliosidosis;C0086652:Mucopolysaccharidosis, MPS-IV-B Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 18, 2024This sequence change creates a premature translational stop signal (p.Arg351*) in the GLB1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in GLB1 are known to be pathogenic (PMID: 18524657). This variant is present in population databases (rs72555372, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with GM1-gangliosidosis (PMID: 10841810, 15714521). ClinVar contains an entry for this variant (Variation ID: 941). For these reasons, this variant has been classified as Pathogenic. -
Infantile GM1 gangliosidosis Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsOct 09, 2020This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.57
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Uncertain
0.44
Eigen_PC
Benign
0.21
FATHMM_MKL
Uncertain
0.92
D
MutationTaster
Benign
1.0
A;A;A;A
Vest4
0.97
GERP RS
4.2

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.

Other links and lift over

dbSNP: rs72555372; hg19: chr3-33087629; API