chr2-240877633-G-T

Variant names:

• chr2-240877633-G-T
• rs180177297
• NM_000030.3:c.942+1G>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000030.3(AGXT):​c.942+1G>T variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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)
• Consequence: AGXT NM_000030.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 3.53
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• alanine glyoxylate aminotransferase deficiency

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• primary hyperoxaluria type 1

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Myriad Women’s Health, Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.08142494 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-240877633-G-T is Pathogenic according to our data. Variant chr2-240877633-G-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 204161.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AGXT	NM_000030.3	c.942+1G>T		splice_donor_variant, intron_variant	Intron 9 of 10	ENST00000307503.4	NP_000021.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AGXT	ENST00000307503.4	c.942+1G>T		splice_donor_variant, intron_variant	Intron 9 of 10	1	NM_000030.3	ENSP00000302620.3
AGXT	ENST00000470255.1	n.720+1G>T		splice_donor_variant, intron_variant	Intron 1 of 2	2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Oct 15, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Disruption of this splice site has been observed in individual(s) with hyperoxaluria (PMID: 15849466). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 204161). This variant is also known as IVS9+1G>T. This variant is not present in population databases (ExAC no frequency). This sequence change affects a donor splice site in intron 9 of the AGXT gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in AGXT are known to be pathogenic (PMID: 19479957). -

May 23, 2022

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Canonical splice site variant expected to result in aberrant splicing, although in the absence of functional evidence the actual effect of this sequence change is unknown.; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25525159, 31152479, 15849466) -

Primary hyperoxaluria, type I Pathogenic:1

Nov 27, 2014

Clinical Biochemistry Laboratory, Health Services Laboratory

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Benign	-0.090
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Pathogenic	0.90
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Uncertain	0.95	D
PhyloP100		3.5
GERP RS		4.3
Mutation Taster		=12/88	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.90
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: -1

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

Other links and lift over

dbSNP: rs180177297; hg19: chr2-241817050;