rs762387914

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_054012.4(ASS1):​c.814C>T​(p.Arg272Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000178 in 1,461,816 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R272L) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

ASS1
NM_054012.4 missense

Scores

11
7
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 5.50

Publications

7 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: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 uncertain in NM_054012.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr9-130480426-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2679049.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
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, 0.993
PP5
Variant 9-130480425-C-T is Pathogenic according to our data. Variant chr9-130480425-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 371132.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
ASS1NM_054012.4 linkc.814C>T p.Arg272Cys missense_variant Exon 11 of 15 ENST00000352480.10 NP_446464.1
ASS1NM_000050.4 linkc.814C>T p.Arg272Cys missense_variant Exon 12 of 16 NP_000041.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ASS1ENST00000352480.10 linkc.814C>T p.Arg272Cys missense_variant Exon 11 of 15 1 NM_054012.4 ENSP00000253004.6

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251282
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1461816
Hom.:
0
Cov.:
33
AF XY:
0.0000206
AC XY:
15
AN XY:
727200
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000153
AC:
17
AN:
1112006
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.448
Heterozygous variant carriers
0
2
4
5
7
9
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
Cov.:
33
Alfa
AF:
0.0000570
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Citrullinemia type I Pathogenic:4
Jul 07, 2016
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. -

Feb 07, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 05, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 30, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Citrullinemia Pathogenic:1
Jan 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 272 of the ASS1 protein (p.Arg272Cys). This variant is present in population databases (rs762387914, gnomAD 0.003%). This missense change has been observed in individual(s) with citrullinemia type I with evidence of co-segregation with disease (PMID: 7977368, 12815590, 22768672). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 371132). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on ASS1 protein function. Experimental studies have shown that this missense change affects ASS1 function (PMID: 8792870). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.48
D
BayesDel_noAF
Pathogenic
0.53
CADD
Pathogenic
32
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
1.0
D;D;D
Eigen
Uncertain
0.58
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.90
.;.;D
M_CAP
Pathogenic
0.63
D
MetaRNN
Pathogenic
0.99
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.3
H;H;H
PhyloP100
5.5
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-7.7
D;D;D
REVEL
Pathogenic
0.90
Sift
Uncertain
0.020
D;D;D
Sift4G
Uncertain
0.038
D;D;D
Polyphen
0.79
P;P;P
Vest4
0.99
MutPred
0.98
Loss of MoRF binding (P = 0.0159);Loss of MoRF binding (P = 0.0159);Loss of MoRF binding (P = 0.0159);
MVP
0.98
MPC
0.66
ClinPred
1.0
D
GERP RS
3.7
Varity_R
0.95
gMVP
0.97
Mutation Taster
=2/98
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs762387914; hg19: chr9-133355812; COSMIC: COSV61689665; COSMIC: COSV61689665; API