rs781642238

Positions:

• chr9-35741810-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_020944.3(GBA2):​c.648C>A​(p.Ser216Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,270 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: GBA2 NM_020944.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.52

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.31175786).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GBA2	NM_020944.3	c.648C>A	p.Ser216Arg	missense_variant	4/17	ENST00000378103.7	NP_065995.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GBA2	ENST00000378103.7	c.648C>A	p.Ser216Arg	missense_variant	4/17	1	NM_020944.3	ENSP00000367343	P1
GBA2	ENST00000378094.4	c.648C>A	p.Ser216Arg	missense_variant	4/17	1		ENSP00000367334
GBA2	ENST00000467252.5	n.220C>A		non_coding_transcript_exon_variant	1/13	1
GBA2	ENST00000485259.1	n.227C>A		non_coding_transcript_exon_variant	3/3	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461270 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727014

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: 0.0000464

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 28, 2018

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with GBA2-related disease. This variant is present in population databases (rs781642238, ExAC 0.006%). This sequence change replaces serine with arginine at codon 216 of the GBA2 protein (p.Ser216Arg). The serine residue is moderately conserved and there is a moderate physicochemical difference between serine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.50
BayesDel_addAF	Benign	-0.064	T
BayesDel_noAF	Benign	-0.33
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.64	D;.
Eigen	Benign	0.047
Eigen_PC	Benign	0.16
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.31	T;T
MetaSVM	Benign	-0.70	T
MutationAssessor	Benign	1.8	L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Uncertain	-2.8	D;D
REVEL	Benign	0.061
Sift	Uncertain	0.0070	D;D
Sift4G	Benign	0.063	T;T
Polyphen		0.0010	B;P
Vest4		0.42
MVP		0.65
MPC		0.84
ClinPred		0.96	D
GERP RS		3.7
Varity_R		0.56
gMVP		0.79

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: rs781642238; hg19: chr9-35741807;