NM_000531.6:c.586G>A

Variant names:

• chrX-38403663-G-A
• rs66642398
• NM_000531.6:c.586G>A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000531.6(OTC):​c.586G>A​(p.Asp196Asn) 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D196V) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 22)
• Consequence: OTC NM_000531.6 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 9.54

Genes affected

OTC (HGNC:8512): (ornithine transcarbamylase) This nuclear gene encodes a mitochondrial matrix enzyme. The encoded protein is involved in the urea cycle which functions to detoxify ammonia into urea for excretion. Mutations in this enzyme lead to ornithine transcarbamylase deficiency, which causes hyperammonemia. [provided by RefSeq, May 2022]

ENSG00000250349 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• 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, 0.996
• PP5: Variant X-38403663-G-A is Pathogenic according to our data. Variant chrX-38403663-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 97257.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-38403663-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTC	NM_000531.6	c.586G>A	p.Asp196Asn	missense_variant	Exon 6 of 10	ENST00000039007.5	NP_000522.3
OTC	NM_001407092.1	c.586G>A	p.Asp196Asn	missense_variant	Exon 8 of 12		NP_001394021.1
OTC	XM_017029556.2	c.586G>A	p.Asp196Asn	missense_variant	Exon 6 of 9		XP_016885045.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTC	ENST00000039007.5	c.586G>A	p.Asp196Asn	missense_variant	Exon 6 of 10	1	NM_000531.6	ENSP00000039007.4
ENSG00000250349	ENST00000465127.1	c.172-262458G>A		intron_variant	Intron 3 of 8	5		ENSP00000417050.1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Sep 12, 2024

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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; This variant is associated with the following publications: (PMID: 25297582, 28266016, 33190319, 16786505, 28324312, 32569589, 37146589) -

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GenMed Metabolism Lab

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Ornithine carbamoyltransferase deficiency Pathogenic:1

Feb 15, 2024

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	0.93
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.24
CADD	Pathogenic	29
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.99	D
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	1.0	D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	3.9	H
PrimateAI	Uncertain	0.79	T
PROVEAN	Pathogenic	-5.0	D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.99		Gain of MoRF binding (P = 0.1008);
MVP		1.0
MPC		1.2
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.98
gMVP		0.97

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs66642398; hg19: chrX-38262916;