7-66088823-G-A

Variant names:

• chr7-66088823-G-A
• rs1554327573
• NM_000048.4:c.735G>A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000048.4(ASL):​c.735G>A​(p.Trp245*) variant causes a stop gained change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ASL NM_000048.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.04
• Publications: 0 publications found

Genes affected

ASL (HGNC:746): (argininosuccinate lyase) This gene encodes a member of the lyase 1 family. The encoded protein forms a cytosolic homotetramer and primarily catalyzes the reversible hydrolytic cleavage of argininosuccinate into arginine and fumarate, an essential step in the liver in detoxifying ammonia via the urea cycle. Mutations in this gene result in the autosomal recessive disorder argininosuccinic aciduria, or argininosuccinic acid lyase deficiency. A nontranscribed pseudogene is also located on the long arm of chromosome 22. Alternatively spliced transcript variants encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

ASL Gene-Disease associations (from GenCC):

• argininosuccinic aciduria

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

ENSG00000249319 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 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 7-66088823-G-A is Pathogenic according to our data. Variant chr7-66088823-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 552651.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000048.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASL	NM_000048.4	MANE Select	c.735G>A	p.Trp245*	stop_gained	Exon 11 of 17	NP_000039.2
	ASL	NM_001024943.2		c.735G>A	p.Trp245*	stop_gained	Exon 10 of 16	NP_001020114.1
	ASL	NM_001024944.2		c.735G>A	p.Trp245*	stop_gained	Exon 10 of 15	NP_001020115.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ASL	ENST00000304874.14	TSL:1 MANE Select	c.735G>A	p.Trp245*	stop_gained	Exon 11 of 17	ENSP00000307188.9
	ASL	ENST00000395332.8	TSL:1	c.735G>A	p.Trp245*	stop_gained	Exon 10 of 16	ENSP00000378741.3
	ENSG00000249319	ENST00000450043.2	TSL:5	c.48G>A	p.Trp16*	stop_gained	Exon 2 of 12	ENSP00000396527.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Argininosuccinate lyase deficiency Pathogenic:3

Nov 30, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jun 26, 2017

Counsyl

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

Dec 23, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 552651). This premature translational stop signal has been observed in individual(s) with Argininosuccinate lyase deficiency (PMID: 24166829). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Trp245*) in the ASL gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ASL are known to be pathogenic (PMID: 2263616, 24166829).

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	49
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Uncertain	0.97	D
PhyloP100		7.0
Vest4		0.93
ClinPred		1.0	D
GERP RS		5.8
PromoterAI		0.0050	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.49		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.49		Position offset: 27

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

Other links and lift over

dbSNP: rs1554327573; hg19: chr7-65553810;