rs1374322297

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1PM2PP3PP5

The NM_001875.5(CPS1):c.4274+2T>C variant causes a splice donor change. The variant allele was found at a frequency of 0.00000383 in 1,304,840 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

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

Exomes 𝑓: 0.0000035 ( 0 hom. )

Consequence

CPS1
NM_001875.5 splice_donor

Scores

Splicing: ADA: 0.9982

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 5.53

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]

CPS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PVS1

Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, max_spliceai. No scorers claiming Uncertain. Scorers claiming Benign: dbscSNV1_RF.

PP5

Variant 2-210675842-T-C is Pathogenic according to our data. Variant chr2-210675842-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 556287.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Likely_pathogenic=3}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CPS1	NM_001875.5 linkuse as main transcript	c.4274+2T>C		splice_donor_variant		ENST00000233072.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CPS1	ENST00000233072.10 linkuse as main transcript	c.4274+2T>C		splice_donor_variant		1	NM_001875.5	P1	P31327-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152230

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

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251040

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135658

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000347

AC:

AN:

1152610

Hom.:

Cov.:

AF XY:

0.00000680

AC XY:

AN XY:

588270

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000362

Gnomad4 OTH exome

AF:

0.0000199

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152230

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74384

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:

0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:4Uncertain:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Congenital hyperammonemia, type I

Pathogenic:3Uncertain:1

Likely pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jan 29, 2018	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Invitae	Mar 28, 2018	This sequence change affects a donor splice site in intron 36 of the CPS1 gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with CPS1-related disease. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Donor and acceptor splice site variants typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CPS1 are known to be pathogenic (PMID: 21120950). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 08, 2018	The CPS1 c.4274+2T>C variant occurs in a canonical splice site (donor) and is therefore predicted to disrupt or distort the normal gene product. A literature search was performed for the gene, cDNA change, and amino acid change. No publications were found based on this search. The variant is reported at a frequency of 0.000009 in the European (non-Finnish) population from the Genome Aggregation Database, but this is based on one allele so the variant is presumed to be rare. Based on the variant frequency, disease prevalence, disease penetrance, and inheritance mode this variant could not be ruled out of causing disease. Due to the potential impact of splice donor variants and the lack of clarifying evidence this variant is classified as a variant of unknown significance but suspicious for pathogenicity for carbamoylphosphate synthetase I deficiency. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

Pulmonary hypertension, neonatal, susceptibility to

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

May 12, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.25

Cadd

Pathogenic

Dann

Uncertain

0.99

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.97

FATHMM_MKL

Uncertain

0.89

MutationTaster

Benign

1.0

D;D;D

GERP RS

6.1

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Benign

0.70

SpliceAI score (max)

0.95

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.95

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over