1-155236425-AG-GA

Variant names:

• chr1-155236425-AG-GA
• NM_000157.4:c.1043_1044delCTinsTC
• GBA1 p.Ala348Val

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1 PP2

The NM_000157.4(GBA1):​c.1043_1044delCTinsTC​(p.Ala348Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type MNV, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A348T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: GBA1 NM_000157.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.25
• Publications: 0 publications found

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]

GBA1 Gene-Disease associations (from GenCC):

• Parkinson disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• Gaucher disease

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health, ClinGen
• Gaucher disease perinatal lethal

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Laboratory for Molecular Medicine, G2P
• late-onset Parkinson disease

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
• Gaucher disease type I

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• Gaucher disease type II

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• Gaucher disease type III

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• Gaucher disease-ophthalmoplegia-cardiovascular calcification syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000157.4
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 94 curated pathogenic missense variants (we use a threshold of 10). The gene has 3 curated benign missense variants. Gene score misZ: 1.1739 (below the threshold of 3.09). Trascript score misZ: 2.2879 (below the threshold of 3.09). GenCC associations: The gene is linked to late-onset Parkinson disease, Gaucher disease type I, Gaucher disease type III, Gaucher disease type II, Gaucher disease-ophthalmoplegia-cardiovascular calcification syndrome, Gaucher disease perinatal lethal, Gaucher disease, Parkinson disease.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000157.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBA1	NM_000157.4	MANE Select	c.1043_1044delCTinsTC	p.Ala348Val	missense	N/A	NP_000148.2	P04062-1
	GBA1	NM_001005741.3		c.1043_1044delCTinsTC	p.Ala348Val	missense	N/A	NP_001005741.1	P04062-1
	GBA1	NM_001005742.3		c.1043_1044delCTinsTC	p.Ala348Val	missense	N/A	NP_001005742.1	P04062-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GBA1	ENST00000368373.8	TSL:1 MANE Select	c.1043_1044delCTinsTC	p.Ala348Val	missense	N/A	ENSP00000357357.3	P04062-1
	GBA1	ENST00000327247.9	TSL:1	c.1043_1044delCTinsTC	p.Ala348Val	missense	N/A	ENSP00000314508.5	P04062-1
	GBA1	ENST00000948997.1		c.1109_1110delCTinsTC	p.Ala370Val	missense	N/A	ENSP00000619056.1

Frequencies

GnomAD3 genomes Cov.: 31

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr1-155206216;