rs772782772

Variant names:

• chr2-210612165-C-T
• rs772782772
• NM_001875.5:c.2440C>T

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_001875.5(CPS1):​c.2440C>T​(p.Arg814Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,460,236 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. R814Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: CPS1 NM_001875.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4 U:1
• Conservation: PhyloP100: 0.865
• Publications: 8 publications found

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 Gene-Disease associations (from GenCC):

• carbamoyl phosphate synthetase I deficiency disease

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae), ClinGen, Myriad Women’s Health

ACMG classification

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 3 uncertain in NM_001875.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.94
• PP5: Variant 2-210612165-C-T is Pathogenic according to our data. Variant chr2-210612165-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 556766.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
CPS1	NM_001875.5	c.2440C>T	p.Arg814Trp	missense_variant	Exon 20 of 38	ENST00000233072.10	NP_001866.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CPS1	ENST00000233072.10	c.2440C>T	p.Arg814Trp	missense_variant	Exon 20 of 38	1	NM_001875.5	ENSP00000233072.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251006 AF XY: 0.00

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1460236 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 726476

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33378

American (AMR) AF: 0.00 AC: 0 AN: 44602

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26040

East Asian (EAS) AF: 0.00 AC: 0 AN: 39664

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86236

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1110880

Other (OTH) AF: 0.00 AC: 0 AN: 60274

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0000451184), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Congenital hyperammonemia, type I Pathogenic:3 Uncertain:1

Aug 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense change has been observed in individuals with CPS1 deficiency (PMID: 21120950, 22173106, 28526534; Invitae). This variant is present in population databases (rs772782772, gnomAD 0.0009%). This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 814 of the CPS1 protein (p.Arg814Trp). ClinVar contains an entry for this variant (Variation ID: 556766). For these reasons, this variant has been classified as Pathogenic. 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 expected to disrupt CPS1 protein function. -

Jun 28, 2025

Immunogenetics and Transplant Biology Service, University Hospital "Città della Salute e della Scienza di Torino"

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 28, 2021

Natera, Inc.

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Mar 06, 2018

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. -

Pulmonary hypertension, neonatal, susceptibility to Pathogenic:1

May 16, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Uncertain	24
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.93	.;D;.
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Pathogenic	0.36	D
MetaRNN	Pathogenic	0.94	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.8	.;H;.
PhyloP100		0.86
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-7.9	D;D;D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	.;D;.
Vest4		0.98
MutPred		0.73		.;Loss of disorder (P = 0.0064);.;
MVP		0.98
MPC		0.86
ClinPred		1.0	D
GERP RS		0.30
Varity_R		0.97
gMVP		0.93
Mutation Taster		=5/95	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs772782772; hg19: chr2-211476889; COSMIC: COSV99242192;