Genetic Variant OTC:p.Asp165His (chrX-38401381-G-C) – ACMG Classification: Uncertain_significance (4 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PP3_Strong

The NM_000531.6(OTC):c.493G>C(p.Asp165His) variant causes a missense change. The variant allele was found at a frequency of 0.00000332 in 1,205,362 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 2 hemizygotes in GnomAD. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000089 ( 0 hom., 1 hem., cov: 23)

Exomes 𝑓: 0.0000027 ( 0 hom. 1 hem. )

Consequence

OTC
NM_000531.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 6.52

Variant links:

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]

OTC links:

ENSG00000250349 (HGNC:):

ENSG00000250349 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTC	NM_000531.6 link	c.493G>C	p.Asp165His	missense_variant	Exon 5 of 10	ENST00000039007.5	NP_000522.3	P00480
OTC	NM_001407092.1 link	c.493G>C	p.Asp165His	missense_variant	Exon 7 of 12		NP_001394021.1
OTC	XM_017029556.2 link	c.493G>C	p.Asp165His	missense_variant	Exon 5 of 9		XP_016885045.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTC	ENST00000039007.5 link	c.493G>C	p.Asp165His	missense_variant	Exon 5 of 10	1	NM_000531.6	ENSP00000039007.4		P00480
ENSG00000250349	ENST00000465127.1 link	c.172-264740G>C		intron_variant	Intron 3 of 8	5		ENSP00000417050.1		B4E171

Frequencies

GnomAD3 genomes

AF:

0.00000894

AC:

AN:

111911

Hom.:

Cov.:

AF XY:

0.0000293

AC XY:

AN XY:

34087

show subpopulations

Gnomad AFR

AF:

0.0000324

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000546

AC:

AN:

183282

Hom.:

AF XY:

0.00

AC XY:

AN XY:

67766

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000365

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1093451

Hom.:

Cov.:

AF XY:

0.00000279

AC XY:

AN XY:

358945

show subpopulations

Gnomad4 AFR exome

AF:

0.0000380

Gnomad4 AMR exome

AF:

0.0000284

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:

0.00000119

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000894

AC:

AN:

111911

Hom.:

Cov.:

AF XY:

0.0000293

AC XY:

AN XY:

34087

show subpopulations

Gnomad4 AFR

AF:

0.0000324

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:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Ornithine carbamoyltransferase deficiency

Uncertain:1

Dec 16, 2023

Mendelics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Uncertain:1

Apr 29, 2024

GeneDx

Significance: Uncertain significance

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; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.85

BayesDel_addAF

Pathogenic

0.60

BayesDel_noAF

Pathogenic

0.73

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.96

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

0.99

M_CAP

Pathogenic

0.92

MetaRNN

Pathogenic

0.99

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

3.4

PrimateAI

Uncertain

0.65

PROVEAN

Pathogenic

-6.2

REVEL

Pathogenic

0.94

Sift

Uncertain

0.016

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.82

MutPred

0.93

Loss of stability (P = 0.2701);

MVP

0.98

MPC

1.3

ClinPred

0.97

GERP RS

6.0

Varity_R

0.95

gMVP

0.96

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

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