rs28934274

Positions:

chr3-33068849-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PS1_ModeratePM2PP3_StrongPP5_Very_Strong

The NM_000404.4(GLB1):c.367G>A(p.Gly123Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000752 in 1,461,836 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/19 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin UniProt.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

GLB1
NM_000404.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.83

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]

GLB1 links:

GLB1 (HGNC:):

GLB1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PS1

Transcript NM_000404.4 (GLB1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in UniProt

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.977

PP5

Variant 3-33068849-C-T is Pathogenic according to our data. Variant chr3-33068849-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 928.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
GLB1	NM_000404.4 linkuse as main transcript	c.367G>A	p.Gly123Arg	missense_variant	3/16	ENST00000307363.10	NP_000395.3	P16278

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GLB1	ENST00000307363.10 linkuse as main transcript	c.367G>A	p.Gly123Arg	missense_variant	3/16	1	NM_000404.4	ENSP00000306920.4		P16278

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000802

AC:

AN:

249506

Hom.:

AF XY:

0.0000148

AC XY:

AN XY:

135360

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000883

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000752

AC:

AN:

1461836

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

727220

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:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000899

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000378

Asia WGS

AF:

0.000866

AC:

AN:

3478

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Mucopolysaccharidosis, MPS-IV-B

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Oct 22, 2024

Variant summary: GLB1 c.367G>A (p.Gly123Arg) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 249506 control chromosomes. c.367G>A has been reported in the literature in individuals affected with Mucopolysaccharidosis Type IVB (Morquio Syndrome B) (examples: Caciotti_2007, Yoshida_1991, Sohn_2012, Lee_2014). These data indicate that the variant is likely to be associated with disease. In vitro functional studies reduced activity for the variant (Yoshida_1991). The following publications have been ascertained in the context of this evaluation (PMID: 17221873, 1907800, 22371915, 25326637). ClinVar contains an entry for this variant (Variation ID: 928). Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 13, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 25364648, 1907800, 32071837, Cho2021[Review], 30665703, 33240792, 31367523, 22371915, 25936995, 30548430, 17221873) -

GM1 gangliosidosis;C0086652:Mucopolysaccharidosis, MPS-IV-B

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 09, 2023

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 123 of the GLB1 protein (p.Gly123Arg). This variant is present in population databases (rs28934274, gnomAD 0.003%). This missense change has been observed in individual(s) with GLB1-related conditions (PMID: 1907800, 17221873, 22371915, 25936995). 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: 928). 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 expected to disrupt GLB1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects GLB1 function (PMID: 1907800). For these reasons, this variant has been classified as Pathogenic. -

Infantile GM1 gangliosidosis

Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Aug 01, 1991

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.95

BayesDel_addAF

Pathogenic

0.51

BayesDel_noAF

Pathogenic

0.59

CADD

Pathogenic

DANN

Pathogenic

1.0

Eigen

Pathogenic

0.90

Eigen_PC

Pathogenic

0.71

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

1.0

.;.;D

M_CAP

Pathogenic

0.79

MetaRNN

Pathogenic

0.98

D;D;D

MetaSVM

Pathogenic

0.97

PrimateAI

Pathogenic

0.84

PROVEAN

Pathogenic

-7.6

D;D;D

REVEL

Pathogenic

0.98

Sift

Pathogenic

0.0

D;D;D

Sift4G

Pathogenic

0.0010

D;D;.

Vest4

0.99

MutPred

0.97

Gain of sheet (P = 0.0827);.;.;

MVP

0.97

MPC

0.95

ClinPred

1.0

GERP RS

4.0

RBP_binding_hub_radar

0.97

RBP_regulation_power_radar

2.8

gMVP

1.0

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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