rs750431938

Variant names:

• chr7-66089147-G-A
• rs750431938
• NM_000048.4:c.890G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP3_Strong PP5

The NM_000048.4(ASL):​c.890G>A​(p.Arg297Gln) variant causes a missense change. The variant allele was found at a frequency of 0.00000616 in 1,461,694 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R297W) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: ASL NM_000048.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 5.07

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]

ENSG00000249319 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-66089146-C-T is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.991
• PP5: Variant 7-66089147-G-A is Pathogenic according to our data. Variant chr7-66089147-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 554299.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ASL	NM_000048.4	c.890G>A	p.Arg297Gln	missense_variant	Exon 12 of 17	ENST00000304874.14	NP_000039.2
ASL	NM_001024943.2	c.890G>A	p.Arg297Gln	missense_variant	Exon 11 of 16		NP_001020114.1
ASL	NM_001024944.2	c.890G>A	p.Arg297Gln	missense_variant	Exon 11 of 15		NP_001020115.1
ASL	NM_001024946.2	c.812G>A	p.Arg271Gln	missense_variant	Exon 10 of 15		NP_001020117.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ASL	ENST00000304874.14	c.890G>A	p.Arg297Gln	missense_variant	Exon 12 of 17	1	NM_000048.4	ENSP00000307188.9
ENSG00000249319	ENST00000450043.2	c.203G>A	p.Arg68Gln	missense_variant	Exon 3 of 12	5		ENSP00000396527.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000798 AC: 2 AN: 250734 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135790

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461694 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 727168

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: 0.00000719

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000223 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Argininosuccinate lyase deficiency Pathogenic:2 Uncertain:1

Sep 15, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant disrupts the p.Arg297 amino acid residue in ASL. Other variant(s) that disrupt this residue have been observed in individuals with ASL-related conditions (PMID: 12384776), which suggests that this may be a clinically significant amino acid residue. Experimental studies have shown that this missense change affects ASL function (PMID: 19703900). 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 expected to disrupt ASL protein function. ClinVar contains an entry for this variant (Variation ID: 554299). This missense change has been observed in individual(s) with argininosuccinate lyase deficiency (PMID: 19703900). This variant is present in population databases (rs750431938, gnomAD 0.002%). This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 297 of the ASL protein (p.Arg297Gln). -

Oct 24, 2017

Counsyl

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 03, 2024

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

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: ASL c.890G>A (p.Arg297Gln) results in a conservative amino acid change in 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 8e-06 in 250734 control chromosomes (gnomAD). c.890G>A has been reported in the literature in individuals affected with argininosuccinic aciduria (example: Trevisson_2009, Gorukmez_2023) . These data indicate that the variant may be associated with disease. In a yeast-based functional complementation assay, the variant showed reduced activity (example: Trevisson_2009). The following publications have been ascertained in the context of this evaluation (PMID: 24166829, 36964972, 19703900). ClinVar contains an entry for this variant (Variation ID: 554299). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.84
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D;.;D;D;.;.
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	1.0	.;D;D;D;D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H;.;H;.;H;.
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.8	D;D;D;D;D;.
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D;D;D;D;D;.
Sift4G	Uncertain	0.023	D;D;D;D;D;D
Polyphen		0.89	P;.;P;.;.;.
Vest4		0.96
MutPred		0.98		Gain of ubiquitination at K299 (P = 0.0356);.;Gain of ubiquitination at K299 (P = 0.0356);.;Gain of ubiquitination at K299 (P = 0.0356);.;
MVP		0.98
MPC		0.52
ClinPred		1.0	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.89

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs750431938; hg19: chr7-65554134;