2-240875973-TGA-TGAGA

Position:

• chr2-240875973-TGA-TGAGA

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000030.3(AGXT):​c.823_824dupAG​(p.Ser275fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,868 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: AGXT NM_000030.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 0.510

Genes affected

AGXT (HGNC:341): (alanine--glyoxylate aminotransferase) This gene is expressed only in the liver and the encoded protein is localized mostly in the peroxisomes, where it is involved in glyoxylate detoxification. Mutations in this gene, some of which alter subcellular targetting, have been associated with type I primary hyperoxaluria. [provided by RefSeq, Jul 2008]

AGXT (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-240875973-T-TGA is Pathogenic according to our data. Variant chr2-240875973-T-TGA is described in ClinVar as [Pathogenic]. Clinvar id is 204201.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AGXT	NM_000030.3	c.823_824dupAG	p.Ser275fs	frameshift_variant	8/11	ENST00000307503.4	NP_000021.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AGXT	ENST00000307503.4	c.823_824dupAG	p.Ser275fs	frameshift_variant	8/11	1	NM_000030.3	ENSP00000302620.3
AGXT	ENST00000476698.1	n.475_476dupAG		non_coding_transcript_exon_variant	4/4	5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251344 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135890

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000163

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461868 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000756

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Primary hyperoxaluria, type I Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 28, 2024	- -
Pathogenic, no assertion criteria provided	clinical testing	Chinese Inherited Urolithiasis Consortium, The Affiliated Yantai Yuhuangding Hospital of Qingdao University	Aug 26, 2024	Variant_type:truncating/MutationTaster:NONE/CADD:NONE/phyloP:NONE/phastCons:NONE/gnomAD_exome_EastAsian:NONE/ExAC_EastAsian:NONE/dbSNP:NONE -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Jul 17, 2023	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with primary hyperoxaluria type 1 (MIM#259900). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0115 - Variants in this gene are known to have variable expressivity, with intrafamilial variability reported (GeneReviews). (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (3 heterozygotes, 0 homozygotes). (SP) 0701 - Other NMD-predicted variants comparable to the one identified in this case have very strong previous evidence for pathogenicity (DECIPHER). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been reported several times as pathogenic, and observed in both compound heterozygous and homozygous individuals with primary hyperoxaluria, bilateral stones and a UTI. Two of these individuals also had haematuria (PMID: 37139236, ClinVar). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Pathogenic, no assertion criteria provided	research	Clinical Biochemistry Laboratory, Health Services Laboratory	Nov 27, 2014	- -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Oct 19, 2020	- -

Primary hyperoxaluria Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Nov 30, 2018

Variant summary: AGXT c.823_824dupAG (p.Ser275ArgfsX38) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 1.2e-05 in 246216 control chromosomes (gnomAD). c.823_824dupAG has been reported in the literature in individuals affected with Primary Hyperoxaluria Type 1 (Chen_2015, Cui_2017, Li_2014, Yuen_2004). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 11, 2023

This sequence change creates a premature translational stop signal (p.Ser275Argfs*38) in the AGXT gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in AGXT are known to be pathogenic (PMID: 19479957). This variant is present in population databases (rs747071948, gnomAD 0.02%). This premature translational stop signal has been observed in individual(s) with primary hyperoxaluria type 1 (PMID: 26252291, 30541997). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is also known as c.824_825insAG and c.815_816insGA. ClinVar contains an entry for this variant (Variation ID: 204201). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs180177273; hg19: chr2-241815390;