2-210650422-C-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong

The NM_001875.5(CPS1):​c.3464C>T​(p.Ala1155Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,612,170 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A1155E) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

CPS1
NM_001875.5 missense

Scores

14
4
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 6.83
Variant links:
Genes affected
CPS1 (HGNC:2323): (carbamoyl-phosphate synthase 1) The mitochondrial enzyme encoded by this gene catalyzes synthesis of carbamoyl phosphate from ammonia and bicarbonate. This reaction is the first committed step of the urea cycle, which is important in the removal of excess urea from cells. The encoded protein may also represent a core mitochondrial nucleoid protein. Three transcript variants encoding different isoforms have been found for this gene. The shortest isoform may not be localized to the mitochondrion. Mutations in this gene have been associated with carbamoyl phosphate synthetase deficiency, susceptibility to persistent pulmonary hypertension, and susceptibility to venoocclusive disease after bone marrow transplantation.[provided by RefSeq, May 2010]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PM1
In a domain ATP-grasp 2 (size 191) in uniprot entity CPSM_HUMAN there are 29 pathogenic changes around while only 4 benign (88%) in NM_001875.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.952

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CPS1NM_001875.5 linkuse as main transcriptc.3464C>T p.Ala1155Val missense_variant 28/38 ENST00000233072.10 NP_001866.2 P31327-1A0A024R454Q6PEK7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CPS1ENST00000233072.10 linkuse as main transcriptc.3464C>T p.Ala1155Val missense_variant 28/381 NM_001875.5 ENSP00000233072.5 P31327-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152104
Hom.:
0
Cov.:
32
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
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251332
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135836
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1460066
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
726472
show subpopulations
Gnomad4 AFR exome
AF:
0.0000598
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152104
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74296
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Congenital hyperammonemia, type I Uncertain:3
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 27, 2022This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1155 of the CPS1 protein (p.Ala1155Val). This variant is present in population databases (rs766125631, gnomAD 0.003%). This missense change has been observed in individual(s) with carbamoyl phosphate synthetase I deficiency (PMID: 21120950). ClinVar contains an entry for this variant (Variation ID: 477855). 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 CPS1 protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
Uncertain significance, criteria provided, single submitterclinical testingCounsylOct 27, 2017- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 23, 2022Variant summary: CPS1 c.3464C>T (p.Ala1155Val) results in a non-conservative amino acid change located in the ATP-binding domain (IPR005479) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251332 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.3464C>T has been reported in the literature in at least one individual affected with Carbamoylphosphate Synthetase I Deficiency (e.g. Haberle_2011). This report does not provide unequivocal conclusions about association of the variant with Carbamoylphosphate Synthetase I Deficiency. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxNov 11, 2023Identified in an individual with suspected CPS1 deficiency, however, clinical information was not provided and a second CPS1 variant was not identified by sequence analysis (PMID: 21120950); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; In silico analysis suggests this variant may impact gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; This variant is associated with the following publications: (PMID: 34426522, 21120950) -
Pulmonary hypertension, neonatal, susceptibility to Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingBaylor GeneticsJan 15, 2024- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Pathogenic
0.49
D
BayesDel_noAF
Pathogenic
0.56
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.93
.;D;.
Eigen
Pathogenic
0.90
Eigen_PC
Pathogenic
0.86
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.97
D;D;D
M_CAP
Uncertain
0.27
D
MetaRNN
Pathogenic
0.95
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
.;M;.
PrimateAI
Uncertain
0.77
T
PROVEAN
Uncertain
-3.6
D;D;D
REVEL
Pathogenic
0.92
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0010
D;D;D
Polyphen
1.0
.;D;.
Vest4
0.94
MutPred
0.78
.;Gain of ubiquitination at K1150 (P = 0.0725);.;
MVP
0.93
MPC
0.84
ClinPred
1.0
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.89
gMVP
0.90

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.25
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.25
Position offset: -2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs766125631; hg19: chr2-211515146; COSMIC: COSV51821318; COSMIC: COSV51821318; API