chrX-38352331-A-G

Position:

• chrX-38352331-A-G

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_001407092.1(OTC):​c.-79-287A>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00345 in 111,999 control chromosomes in the GnomAD database, including 1 homozygotes. There are 94 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency: Genomes: 𝑓 0.0034 (1 hom., 94 hem., cov: 24)
• Consequence: OTC NM_001407092.1 intron
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:6
• Conservation: PhyloP100: 2.09

Genes affected

ENSG00000250349 (HGNC:):

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]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant X-38352331-A-G is Benign according to our data. Variant chrX-38352331-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 516756.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-38352331-A-G is described in Lovd as [Pathogenic].
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00345 (386/111999) while in subpopulation NFE AF= 0.00577 (307/53225). AF 95% confidence interval is 0.00524. There are 1 homozygotes in gnomad4. There are 94 alleles in male gnomad4 subpopulation. Median coverage is 24. This position pass quality control queck.
• BS2: High Hemizygotes in GnomAd4 at 94 XL gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
OTC	NM_001407092.1	c.-79-287A>G		intron_variant			NP_001394021.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ENSG00000250349	ENST00000465127.1	c.172-313790A>G		intron_variant		5		ENSP00000417050.1

Frequencies

GnomAD3 genomes AF: 0.00345 AC: 386 AN: 111947 Hom.: 1 Cov.: 24 AF XY: 0.00276 AC XY: 94 AN XY: 34095

Gnomad AFR AF: 0.000715

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00238

Gnomad ASJ AF: 0.00189

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000736

Gnomad FIN AF: 0.00313

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00577

Gnomad OTH AF: 0.00401

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00345 AC: 386 AN: 111999 Hom.: 1 Cov.: 24 AF XY: 0.00275 AC XY: 94 AN XY: 34157

Gnomad4 AFR AF: 0.000714

Gnomad4 AMR AF: 0.00237

Gnomad4 ASJ AF: 0.00189

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000738

Gnomad4 FIN AF: 0.00313

Gnomad4 NFE AF: 0.00577

Gnomad4 OTH AF: 0.00396

Alfa AF: 0.00356 Hom.: 19

Bravo AF: 0.00329

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Ornithine carbamoyltransferase deficiency Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Apr 28, 2022	- -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 06, 2023	- -
Benign, no assertion criteria provided	clinical testing	Natera, Inc.	Dec 09, 2019	- -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 23, 2017

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

OTC-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 19, 2022

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Sep 01, 2023

OTC: BS1 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	10
DANN	Benign	0.57

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

Other links and lift over

dbSNP: rs191615506; hg19: chrX-38211584;