rs200268523

chr9-35744349-C-Achr9-35744349-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Moderate PP5_Moderate

The NM_020944.3(GBA2):c.515G>T(p.Arg172Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,364 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 Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R172H) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GBA2 NM_020944.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.92

Genes affected

GBA2 (HGNC:18986): (glucosylceramidase beta 2) This gene encodes a microsomal beta-glucosidase that catalyzes the hydrolysis of bile acid 3-O-glucosides as endogenous compounds. Studies to determine subcellular localization of this protein in the liver indicated that the enzyme was mainly enriched in the microsomal fraction where it appeared to be confined to the endoplasmic reticulum. This putative transmembrane protein is thought to play a role in carbohydrate transport and metabolism. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-35744349-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 810379.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=2}.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.879
• PP5: Variant 9-35744349-C-A is Pathogenic according to our data. Variant chr9-35744349-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 458304.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GBA2	NM_020944.3	c.515G>T	p.Arg172Leu	missense_variant	3/17	ENST00000378103.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GBA2	ENST00000378103.7	c.515G>T	p.Arg172Leu	missense_variant	3/17	1	NM_020944.3	P1
GBA2	ENST00000378094.4	c.515G>T	p.Arg172Leu	missense_variant	3/17	1
GBA2	ENST00000485259.1	n.43G>T		non_coding_transcript_exon_variant	1/3	3
GBA2	ENST00000489025.1	n.784G>T		non_coding_transcript_exon_variant	3/3	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461364 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 727018

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Sep 19, 2022

This variant disrupts the p.Arg172 amino acid residue in GBA2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 32590105; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on GBA2 protein function. ClinVar contains an entry for this variant (Variation ID: 458304). This missense change has been observed in individuals with clinical features of hereditary spastic paraplegia (Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 172 of the GBA2 protein (p.Arg172Leu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
Cadd	Pathogenic	31
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.70	D;.
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.44
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Benign	0.036	D
MetaRNN	Pathogenic	0.88	D;D
MetaSVM	Benign	-0.73	T
MutationAssessor	Benign	1.3	L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-5.6	D;D
REVEL	Uncertain	0.42
Sift	Uncertain	0.0030	D;D
Sift4G	Uncertain	0.0040	D;D
Polyphen		1.0	D;D
Vest4		0.94
MutPred		0.57		Loss of MoRF binding (P = 0.0171);Loss of MoRF binding (P = 0.0171);
MVP		0.68
MPC		1.1
ClinPred		1.0	D
GERP RS		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.79
gMVP		0.90

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

Publications

LitVar

Other links and lift over

dbSNP: rs200268523; hg19: chr9-35744346;