rs180177285

chr2-240877536-G-C

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_000030.3(AGXT):c.847-1G>C variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000287 in 1,395,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000029 (0 hom.)
• Consequence: AGXT NM_000030.3 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.64

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]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.08057676 fraction of the gene. Cryptic splice site detected, with MaxEntScore 4.8, offset of -17, new splice context is: cccatgtcactgcccaccAGcgc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 2-240877536-G-C is Pathogenic according to our data. Variant chr2-240877536-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 204168.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AGXT	NM_000030.3	c.847-1G>C		splice_acceptor_variant		ENST00000307503.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AGXT	ENST00000307503.4	c.847-1G>C		splice_acceptor_variant		1	NM_000030.3	P1
AGXT	ENST00000470255.1	n.624G>C		non_coding_transcript_exon_variant	1/3	2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000287 AC: 4 AN: 1395488 Hom.: 0 Cov.: 31 AF XY: 0.00000291 AC XY: 2 AN XY: 687938

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000371

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Primary hyperoxaluria, type I Pathogenic:3

Pathogenic, no assertion criteria provided	research	Clinical Biochemistry Laboratory, Health Services Laboratory	Nov 27, 2014	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Aug 04, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 01, 2023	- -

Primary hyperoxaluria Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

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

Nov 02, 2020

Variant summary: AGXT c.847-1G>C alters a conserved nucleotide located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Four predict the variant abolishes a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 151426 control chromosomes. c.847-1G>C has been reported in the literature in individuals affected with Primary Hyperoxaluria Type 1 and subsequently cited by others (example, Basmaison_2000, Fargue_2009, Coulter-Mackie_2004, Pirulli_2003, Williams_2009, Mandrile_2014). 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. 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 likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Uncertain	0.10
Cadd	Pathogenic	34
Dann	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Uncertain	0.97	D
MutationTaster	Benign	1.0	A
GERP RS		4.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.59		Position offset: -16
DS_AL_spliceai		0.99		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs180177285; hg19: chr2-241816953;