9-130494900-G-A

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM2PM5PP2PP3_ModeratePP5_Moderate

The NM_054012.4(ASS1):​c.1004G>A​(p.Arg335His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000211 in 1,613,408 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 Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R335C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

ASS1
NM_054012.4 missense

Scores

9
7
3

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1U:1

Conservation

PhyloP100: 7.46

Publications

3 publications found
Variant links:
Genes affected
ASS1 (HGNC:758): (argininosuccinate synthase 1) The protein encoded by this gene catalyzes the penultimate step of the arginine biosynthetic pathway. There are approximately 10 to 14 copies of this gene including the pseudogenes scattered across the human genome, among which the one located on chromosome 9 appears to be the only functional gene for argininosuccinate synthetase. Mutations in the chromosome 9 copy of this gene cause citrullinemia. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Aug 2012]
ASS1 Gene-Disease associations (from GenCC):
  • citrullinemia type I
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Myriad Women’s Health, G2P
  • acute neonatal citrullinemia type I
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • adult-onset citrullinemia type I
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 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 chr9-130494899-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 528370.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 49 curated pathogenic missense variants (we use a threshold of 10). The gene has 4 curated benign missense variants. Gene score misZ: 0.75759 (below the threshold of 3.09). Trascript score misZ: 1.8061 (below the threshold of 3.09). GenCC associations: The gene is linked to citrullinemia type I, adult-onset citrullinemia type I, acute neonatal citrullinemia type I.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.885
PP5
Variant 9-130494900-G-A is Pathogenic according to our data. Variant chr9-130494900-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 555009.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ASS1NM_054012.4 linkc.1004G>A p.Arg335His missense_variant Exon 13 of 15 ENST00000352480.10 NP_446464.1 P00966Q5T6L4
ASS1NM_000050.4 linkc.1004G>A p.Arg335His missense_variant Exon 14 of 16 NP_000041.2 P00966Q5T6L4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ASS1ENST00000352480.10 linkc.1004G>A p.Arg335His missense_variant Exon 13 of 15 1 NM_054012.4 ENSP00000253004.6 P00966
ASS1ENST00000372393.7 linkc.1004G>A p.Arg335His missense_variant Exon 14 of 16 5 ENSP00000361469.2 P00966
ASS1ENST00000372394.5 linkc.1004G>A p.Arg335His missense_variant Exon 14 of 16 2 ENSP00000361471.1 P00966
ASS1ENST00000372386.6 linkn.275G>A non_coding_transcript_exon_variant Exon 4 of 6 3

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152174
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000518
AC:
13
AN:
251166
AF XY:
0.0000516
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000145
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1461116
Hom.:
0
Cov.:
31
AF XY:
0.0000220
AC XY:
16
AN XY:
726872
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33462
American (AMR)
AF:
0.000112
AC:
5
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86222
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53376
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5352
European-Non Finnish (NFE)
AF:
0.0000171
AC:
19
AN:
1111846
Other (OTH)
AF:
0.00
AC:
0
AN:
60312
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000525
AC:
8
AN:
152292
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74464
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41572
American (AMR)
AF:
0.00
AC:
0
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.000148
Hom.:
0
Bravo
AF:
0.0000567
ExAC
AF:
0.0000165
AC:
2
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Citrullinemia Pathogenic:1
Jul 20, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 335 of the ASS1 protein (p.Arg335His). This variant is present in population databases (rs555388438, gnomAD 0.01%). This missense change has been observed in individual(s) with citrullinemia and/or elevated citrulline (PMID: 28111830, 31737040; 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: 555009). 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 not expected to disrupt ASS1 protein function with a negative predictive value of 80%. This variant disrupts the p.Arg335 amino acid residue in ASS1. Other variant(s) that disrupt this residue have been determined to be pathogenic (Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Citrullinemia type I Uncertain:1
Nov 10, 2017
Counsyl
Significance:Uncertain significance
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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.23
BayesDel_addAF
Pathogenic
0.29
D
BayesDel_noAF
Pathogenic
0.44
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.96
D;D;D
Eigen
Pathogenic
0.72
Eigen_PC
Pathogenic
0.69
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.84
.;.;T
M_CAP
Uncertain
0.20
D
MetaRNN
Pathogenic
0.88
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.7
M;M;M
PhyloP100
7.5
PrimateAI
Uncertain
0.75
T
PROVEAN
Uncertain
-3.6
D;D;D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.025
D;D;D
Sift4G
Uncertain
0.030
D;D;D
Polyphen
1.0
D;D;D
Vest4
0.81
MVP
0.98
MPC
0.48
ClinPred
0.74
D
GERP RS
4.8
Varity_R
0.73
gMVP
0.78
Mutation Taster
=4/96
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs555388438; hg19: chr9-133370287; API