NM_000048.4:c.740C>T

Variant names:

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1PM2PP2PP3_StrongPP5

The NM_000048.4(ASL):c.740C>T(p.Ser247Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,613,670 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). Synonymous variant affecting the same amino acid position (i.e. S247S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

ASL
NM_000048.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 7.30

Publications

1 publications found

Variant links:

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

ASL links:

ENSG00000249319 (HGNC:):

ENSG00000249319 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 10 ACMG points.

PM1

In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000048.4

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 95 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 0.7488 (below the threshold of 3.09). Trascript score misZ: 1.388 (below the threshold of 3.09). GenCC associations: The gene is linked to argininosuccinic aciduria.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.947

PP5

Variant 7-66088828-C-T is Pathogenic according to our data. Variant chr7-66088828-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 459922.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein
ASL	NM_000048.4 link	c.740C>T	p.Ser247Leu	missense_variant	Exon 11 of 17	ENST00000304874.14	NP_000039.2
ASL	NM_001024943.2 link	c.740C>T	p.Ser247Leu	missense_variant	Exon 10 of 16		NP_001020114.1
ASL	NM_001024944.2 link	c.740C>T	p.Ser247Leu	missense_variant	Exon 10 of 15		NP_001020115.1
ASL	NM_001024946.2 link	c.662C>T	p.Ser221Leu	missense_variant	Exon 9 of 15		NP_001020117.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ASL	ENST00000304874.14 link	c.740C>T	p.Ser247Leu	missense_variant	Exon 11 of 17	1	NM_000048.4	ENSP00000307188.9
ENSG00000249319	ENST00000450043.2 link	c.53C>T	p.Ser18Leu	missense_variant	Exon 2 of 12	5		ENSP00000396527.2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152174

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000120

AC:

AN:

250634

AF XY:

0.0000148

show subpopulations

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 FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000265

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000116

AC:

AN:

1461496

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

726970

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33476

American (AMR)

AF:

0.00

AC:

AN:

44690

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26104

East Asian (EAS)

AF:

0.00

AC:

AN:

39698

South Asian (SAS)

AF:

0.0000116

AC:

AN:

86094

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53386

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000135

AC:

AN:

1111904

Other (OTH)

AF:

0.0000166

AC:

AN:

60376

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.454

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74328

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41452

American (AMR)

AF:

0.00

AC:

AN:

15254

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5188

South Asian (SAS)

AF:

0.00

AC:

AN:

4836

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10618

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68036

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.425

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000756

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Argininosuccinate lyase deficiency

Pathogenic:2

Jan 17, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Pathogenic

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 247 of the ASL protein (p.Ser247Leu). This variant is present in population databases (no rsID available, gnomAD 0.003%). This missense change has been observed in individual(s) with argininosuccinate lyase deficiency (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 459922). 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 with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Jun 09, 2025

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.740C>T (p.Ser247Leu) results in a non-conservative amino acid change located in the Fumarate lyase, N-terminal domain (IPR022761) of the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 1.2e-05 in 250634 control chromosomes. c.740C>T has been observed in individual(s) affected with or with clinical features of Argininosuccinic Aciduria (internal data). 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. ClinVar contains an entry for this variant (Variation ID: 459922). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided

Uncertain:1

May 06, 2021

GeneDx

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.54

BayesDel_addAF

Pathogenic

0.42

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.97

D;.;D;D;.;.

Eigen

Pathogenic

0.73

Eigen_PC

Pathogenic

0.73

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.99

.;D;D;D;D;D

M_CAP

Pathogenic

0.97

MetaRNN

Pathogenic

0.95

D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.3

M;.;M;.;M;.

PhyloP100

7.3

PrimateAI

Uncertain

0.66

PROVEAN

Pathogenic

-4.6

D;D;D;D;D;.

REVEL

Pathogenic

0.88

Sift

Uncertain

0.0010

D;D;D;D;D;.

Sift4G

Benign

0.068

T;T;T;T;T;D

Polyphen

0.96

D;.;D;.;.;.

Vest4

0.75

MutPred

0.77

Loss of catalytic residue at S247 (P = 0.0381);.;Loss of catalytic residue at S247 (P = 0.0381);.;Loss of catalytic residue at S247 (P = 0.0381);.;

MVP

0.99

MPC

0.67

ClinPred

0.98

GERP RS

5.8

PromoterAI

-0.031

Neutral

(source)

RBP_binding_hub_radar

0.92

RBP_regulation_power_radar

2.0

Varity_R

0.89

gMVP

0.94

Mutation Taster

=10/90

disease causing (ClinVar)

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.11

Details are displayed if max score is > 0.2

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

Publications

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Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over