rs1141812

chr1-155239946-G-Achr1-155239946-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_000157.4(GBA1):c.247C>T(p.Arg83Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000589 in 1,613,990 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000062 (0 hom.)
• Consequence: GBA1 NM_000157.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 3.47

Genes affected

GBA1 (HGNC:4177): (glucosylceramidase beta 1) This gene encodes a lysosomal membrane protein that cleaves the beta-glucosidic linkage of glycosylceramide, an intermediate in glycolipid metabolism. Mutations in this gene cause Gaucher disease, a lysosomal storage disease characterized by an accumulation of glucocerebrosides. A related pseudogene is approximately 12 kb downstream of this gene on chromosome 1. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000157.4
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18886441).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GBA1	NM_000157.4	c.247C>T	p.Arg83Cys	missense_variant	3/11	ENST00000368373.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GBA1	ENST00000368373.8	c.247C>T	p.Arg83Cys	missense_variant	3/11	1	NM_000157.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152118 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.000576

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000836 AC: 21 AN: 251312 Hom.: 0 AF XY: 0.0000663 AC XY: 9 AN XY: 135836

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00119

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000528

Gnomad OTH exome AF: 0.000326

GnomAD4 exome AF: 0.0000622 AC: 91 AN: 1461872 Hom.: 0 Cov.: 33 AF XY: 0.0000495 AC XY: 36 AN XY: 727236

Gnomad4 AFR exome AF: 0.0000896

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00161

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000297

Gnomad4 OTH exome AF: 0.000199

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152118 Hom.: 0 Cov.: 31 AF XY: 0.0000404 AC XY: 3 AN XY: 74316

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.000576

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000900 Hom.: 0

Bravo AF: 0.0000869

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000412 AC: 5

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jul 22, 2021	Reported previously using alternate nomenclature (R44C) in an Ashkenazi Jewish (AJ) individual with essential tremor; however, the authors concluded that there was no evidence for association of GBA variants with essential tremor as the variants were present with similar frequencies in AJ essential tremor patients and AJ controls (Clark et al., 2010); Reported in the heterozygous state in two individuals with Parkinson disease and was absent in controls. One of the individuals was a Parkinson disease patient with no family history who also harbored a variant in the LRRK2 gene (Benitez et al., 2016); In an Ashkenazi Jewish population screening study for GBA variants in Parkinson patients, the frequency of the R83C (reported as R44C) variant was 4 times higher in an in-house control population (7/662) than in the Parkinson disease patient population (2/735); however, the variant was present at a lower frequency in a larger control population derived from the IBD exomes project, suggesting that further studies are needed to better understand the significance of this variant (Ruskey et al., 2018); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Missense variants in nearby residues reported in the Human Gene Mutation Database in individuals with Gaucher disease and Parkinson disease (Stenson et al., 2014) This variant is associated with the following publications: (PMID: 31996268, 29842932, 19815695, 19527940, 27094865, 26117366, 21837367) -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	May 01, 2017	- -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Oct 18, 2021

Variant summary: GBA c.247C>T (p.Arg83Cys), also known as R44C in literatures, results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8.5e-05 in 258476 control chromosomes (gnomAD and publication data). This frequency is not significantly higher than expected for a pathogenic variant in GBA causing Gaucher Disease (8.5e-05 vs 0.005), allowing no conclusion about variant significance. c.247C>T has been reported in the literature in individuals affected with essential tremor, Amyotrophic lateral sclerosis, Dementia with Lewy bodies and Parkinson's disease (Clark_2009, Gan-Or2011, Alcalay_2015, Mata_2016, Benitez_2016, Kruger_2016, Robak_2017, Goldstein_2019, Orme_2020, Mangone_2020). These reports do not provide unequivocal conclusions about association of the variant with disease. Additionally, other missense variants (p.R78H, p.S81N,p.G85E, p.T100M) in nearby residues have been found in individuals affected with Gaucher disease and Parkinson's disease in the Human Gene Mutation Database. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Gaucher disease type II;C0268251:Gaucher disease type III;C0752347:Lewy body dementia;C1842704:Gaucher disease perinatal lethal;C1856476:Gaucher disease-ophthalmoplegia-cardiovascular calcification syndrome;C1961835:Gaucher disease type I;C3160718:Parkinson disease, late-onset Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

May 03, 2022

- -

Gaucher disease Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Aug 09, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Uncertain	0.040	T
BayesDel_noAF	Uncertain	-0.050
Cadd	Pathogenic	32
Dann	Benign	0.97
DEOGEN2	Pathogenic	0.81	D;D;.
Eigen	Benign	-0.35
Eigen_PC	Benign	-0.49
FATHMM_MKL	Benign	0.76	D
M_CAP	Pathogenic	0.30	D
MetaRNN	Benign	0.19	T;T;T
MetaSVM	Uncertain	0.30	D
MutationAssessor	Uncertain	2.4	M;M;M
MutationTaster	Benign	0.98	N;N;N;N;N
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-3.3	D;D;D
REVEL	Uncertain	0.36
Sift	Uncertain	0.0080	D;D;D
Sift4G	Uncertain	0.015	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.40
MVP		0.85
MPC		0.14
ClinPred		0.25	T
GERP RS		1.5
Varity_R		0.42
gMVP		0.62

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

Other links and lift over

dbSNP: rs1141812; hg19: chr1-155209737;