chr1-155238141-A-T
Variant summary
Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM1PM2PP3_ModeratePP5_Very_Strong
The NM_000157.4(GBA1):c.754T>A(p.Phe252Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000204 in 1,614,028 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 (★★).
Frequency
Consequence
NM_000157.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Pathogenic. Variant got 14 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
GBA1 | NM_000157.4 | c.754T>A | p.Phe252Ile | missense_variant | Exon 6 of 11 | ENST00000368373.8 | NP_000148.2 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152156Hom.: 0 Cov.: 30
GnomAD3 exomes AF: 0.0000437 AC: 11AN: 251488Hom.: 0 AF XY: 0.0000368 AC XY: 5AN XY: 135916
GnomAD4 exome AF: 0.0000219 AC: 32AN: 1461872Hom.: 0 Cov.: 32 AF XY: 0.0000261 AC XY: 19AN XY: 727234
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152156Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0AN XY: 74344
ClinVar
Submissions by phenotype
Gaucher disease Pathogenic:3Other:1
The p.Phe2252Ile variant in GBA has been reported in at least 17 individuals with Gaucher disease and has been identified in 0.010% (2/19954) of East Asian chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP rs381737). Although this variant has been seen in the general population, its frequency is low enough to be consistent with a recessive carrier frequency. This variant has also been reported in ClinVar (VariationID: 4301) as pathogenic by EGL Genetic Diagnostics and OMIM. In vitro functional studies provide some evidence that the p.Phe252Ile variant may impact protein function (PMID: 15276648). However, these types of assays may not accurately represent biological function. Computational prediction tools suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. The Phe at position 252 is highly conserved in mammals and evolutionary distant species, but 1 mammal (Chimp) carries an Ile, raising the possibility that this change at this position may be tolerated. The presence of this variant in 4 affected homozygotes and in combination with reported pathogenic variants in 8 individuals with Gaucher disease increases the likelihood that the p.Phe252Ile variant is pathogenic (VariationID: 4296, 4288, 4327, 4328; PMID: 17689991, 20729108, 15954102, 30949558, 30764785, 29685539). The phenotype of individuals homozygous and compound heterozygous for this variant is highly specific for Gaucher disease based on significantly reduced levels of beta-glucosidase in patient leukocytes consistent with disease (PMID: 17689991, 30764785, 15954102). In summary, this variant meets criteria to be classified as pathogenic for Gaucher disease in an autosomal recessive manner based on the presence of the variant in combination with other pathogenic variants, in vitro functional studies, and the phenotype of individuals with the variant being highly specific for Gaucher disease. ACMG/AMP Criteria applied: PM3_very-strong, PS3_moderate, PM2_supporting, PP4 (Richards 2015). -
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Variant summary: GBA c.754T>A (p.Phe252Ile) results in a non-conservative amino acid change located in the Glycosyl hudrolase family 30, TIM-barrel domain (IPR033453) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4.4e-05 in 251488 control chromosomes. This frequency is not significantly higher than expected for a pathogenic variant in GBA causing Gaucher Disease (4.4e-05 vs 0.005), allowing no conclusion about variant significance. c.754T>A has been reported in the literature in multiple individuals from diverse ethnic backgrounds affected with Gaucher Disease, example, Japanese (Kawame_1991), English (He_1992), Italian (Filocamo_1992), Thai (Suwannarat_2007), and Indian (Sheth_2019), in addition to patients affected with Parkinson's disease (example, Trinh_2019). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in <10% of normal activity in transient expression of Glucocerebrosidase activity in transfected COS-1 cells (example, Kawame_1991). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as pathogenic using overlapping evidence utilized in the context of this evaluation. Based on the evidence outlined above, the variant was classified as pathogenic. -
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not provided Pathogenic:3
Published functional studies demonstrate that this variant results in deficient beta-glucocerebrosidase activity (Kawame et al., 1991; Kim et al., 2020); Also described in past literature as p.F213I using alternate nomenclature; This variant is associated with the following publications: (PMID: 32677286, 33176831, 27802905, 15954102, 15276648, 23430543, 20301446, 30764785, 30949558, 19830760, 31637888, 30537300, 12204005, 25435509, 25875285, 29699937, 14984463, 16720474, 17689991, 1840477, 1301953, 29685539, 29140481, 20729108) -
This sequence change replaces phenylalanine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 252 of the GBA protein (p.Phe252Ile). This variant is present in population databases (rs381737, gnomAD 0.01%). This missense change has been observed in individual(s) with Gaucher disease and/or Parkinson's disease (PMID: 1301953, 12204005, 17689991, 29140481). This variant is also known as p.Phe213Ile. ClinVar contains an entry for this variant (Variation ID: 4301). 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 not expected to disrupt GBA protein function with a negative predictive value of 80%. Experimental studies have shown that this missense change affects GBA function (PMID: 1840477). This variant disrupts the p.Phe252 amino acid residue in GBA. Other variant(s) that disrupt this residue have been observed in individuals with GBA-related conditions (PMID: 23430543), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -
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Gaucher disease type I Pathogenic:1
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not specified Pathogenic:1
The p.F252I variant (also known as c.754T>A, p.F213I, and c.3548T>A), located in coding exon 6 of the GBA gene, results from a T to A substitution at nucleotide position 754. The phenylalanine at codon 252 is replaced by isoleucine, an amino acid with highly similar properties. This alteration has been detected in individuals with confirmed diagnoses of Gaucher disease, in both homozygous and compound heterozygous states (Suwannarat P et al. Blood Cells Mol. Dis. Aug;39:348-52; Ortiz-Cabrera NV et al. Mol Genet Metab Rep, 2016 Dec;9:79-85; Santamaria R et al. Hum. Mutat., 2008 Jun;29:E58-67; Tang NL et al. Hum. Mutat., 2005 Jul;26:59-60; Kawame H et al. Am. J. Hum. Genet., 1991 Dec;49:1378-80; Latham TE et al. DNA Cell Biol.;10:15-21). In addition, in one study authors showed that, when this alteration was transfected into COS-1 cells, the glucosidase activity failed to increase as efficiently as normal cDNA (Kawame H et al. Am. J. Hum. Genet., 1991 Dec;49:1378-80). Of note, this alteration has also been detected in GBA pseudogene. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -
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 Pathogenic:1
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Gaucher disease type II Pathogenic:1
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Gaucher disease type III Pathogenic:1
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Lewy body dementia Pathogenic:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at