NM_001875.5:c.2446T>C

Variant names:

• chr2-210612171-T-C
• rs1553513870
• NM_001875.5:c.2446T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001875.5(CPS1):​c.2446T>C​(p.Cys816Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (no stars). Synonymous variant affecting the same amino acid position (i.e. C816C) has been classified as Benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CPS1 NM_001875.5 missense
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 7.41
• Publications: 0 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: Labcorp Genetics (formerly Invitae), ClinGen, Myriad Women’s Health, Orphanet, G2P

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 3 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, 0.884

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001875.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CPS1	NM_001875.5	MANE Select	c.2446T>C	p.Cys816Arg	missense	Exon 20 of 38	NP_001866.2
	CPS1	NM_001369256.1		c.2479T>C	p.Cys827Arg	missense	Exon 21 of 39	NP_001356185.1
	CPS1	NM_001122633.3		c.2446T>C	p.Cys816Arg	missense	Exon 21 of 39	NP_001116105.2	P31327-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CPS1	ENST00000233072.10	TSL:1 MANE Select	c.2446T>C	p.Cys816Arg	missense	Exon 20 of 38	ENSP00000233072.5	P31327-1
	CPS1	ENST00000430249.7	TSL:1	c.2464T>C	p.Cys822Arg	missense	Exon 21 of 39	ENSP00000402608.2	P31327-3
	CPS1	ENST00000451903.3	TSL:1	c.1093T>C	p.Cys365Arg	missense	Exon 10 of 28	ENSP00000406136.2	P31327-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital hyperammonemia, type I (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.46
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Benign	0.75	N
PhyloP100		7.4
PrimateAI	Pathogenic	0.85	D
PROVEAN	Uncertain	-3.5	D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.98	D
Vest4		0.95
MutPred		0.65		Gain of disorder (P = 0.0151)
MVP		0.98
MPC		1.0
ClinPred		0.99	D
GERP RS		5.3
Varity_R		0.97
gMVP		0.97
Mutation Taster		=2/98	disease causing

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

Other links and lift over

dbSNP: rs1553513870; hg19: chr2-211476895; COSMIC: COSV51819769;