rs754062242

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PP2PP3

The NM_054012.4(ASS1):​c.839G>C​(p.Gly280Ala) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,428 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 15/24 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G280V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

ASS1
NM_054012.4 missense, splice_region

Scores

14
4
1
Splicing: ADA: 0.9989
2

Clinical Significance

Uncertain significance no assertion criteria provided U:1

Conservation

PhyloP100: 9.36

Publications

0 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 6 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_054012.4
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 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
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ASS1NM_054012.4 linkc.839G>C p.Gly280Ala missense_variant, splice_region_variant Exon 12 of 15 ENST00000352480.10 NP_446464.1 P00966Q5T6L4
ASS1NM_000050.4 linkc.839G>C p.Gly280Ala missense_variant, splice_region_variant Exon 13 of 16 NP_000041.2 P00966Q5T6L4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ASS1ENST00000352480.10 linkc.839G>C p.Gly280Ala missense_variant, splice_region_variant Exon 12 of 15 1 NM_054012.4 ENSP00000253004.6 P00966

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151732
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251418
AF XY:
0.00000736
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:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461696
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
727166
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53318
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111968
Other (OTH)
AF:
0.00
AC:
0
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000659
AC:
1
AN:
151732
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74052
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41258
American (AMR)
AF:
0.00
AC:
0
AN:
15236
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5168
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4788
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10540
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67968
Other (OTH)
AF:
0.00
AC:
0
AN:
2082
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.725
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: no assertion criteria provided
LINK: link

Submissions by phenotype

Citrullinemia type I Uncertain:1
Mar 11, 2025
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.98
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.46
CADD
Pathogenic
33
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.99
D;D;D
Eigen
Pathogenic
0.95
Eigen_PC
Pathogenic
0.84
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Pathogenic
0.99
.;.;D
M_CAP
Pathogenic
0.55
D
MetaRNN
Pathogenic
0.96
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.7
H;H;H
PhyloP100
9.4
PrimateAI
Pathogenic
0.88
D
PROVEAN
Pathogenic
-5.8
D;D;D
REVEL
Pathogenic
0.94
Sift
Uncertain
0.0030
D;D;D
Sift4G
Uncertain
0.0030
D;D;D
Polyphen
1.0
D;D;D
Vest4
0.94
MutPred
0.77
Loss of ubiquitination at K277 (P = 0.1486);Loss of ubiquitination at K277 (P = 0.1486);Loss of ubiquitination at K277 (P = 0.1486);
MVP
0.99
MPC
0.97
ClinPred
0.99
D
GERP RS
4.5
Varity_R
0.97
gMVP
0.87
Mutation Taster
=15/85
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.85
SpliceAI score (max)
0.050
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: rs754062242; hg19: chr9-133364720; API