chrX-38352702-G-A

Variant names:

• chrX-38352702-G-A
• rs1602008611
• NM_000531.6:c.6G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Moderate BP6_Moderate BP7

The NM_000531.6(OTC):​c.6G>A​(p.Leu2Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000919 in 1,087,711 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. L2L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 9.2e-7 (0 hom. 1 hem.)
• Consequence: OTC NM_000531.6 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.26
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• ornithine carbamoyltransferase deficiency

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P, Laboratory for Molecular Medicine, Orphanet

ENSG00000250349 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant X-38352702-G-A is Benign according to our data. Variant chrX-38352702-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 2727469.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=1.26 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTC	NM_000531.6	c.6G>A	p.Leu2Leu	synonymous_variant	Exon 1 of 10	ENST00000039007.5	NP_000522.3
OTC	NM_001407092.1	c.6G>A	p.Leu2Leu	synonymous_variant	Exon 3 of 12		NP_001394021.1
OTC	XM_017029556.2	c.6G>A	p.Leu2Leu	synonymous_variant	Exon 1 of 9		XP_016885045.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTC	ENST00000039007.5	c.6G>A	p.Leu2Leu	synonymous_variant	Exon 1 of 10	1	NM_000531.6	ENSP00000039007.4
ENSG00000250349	ENST00000465127.1	c.172-313419G>A		intron_variant	Intron 3 of 8	5		ENSP00000417050.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 9.19e-7 AC: 1 AN: 1087711 Hom.: 0 Cov.: 27 AF XY: 0.00000283 AC XY: 1 AN XY: 353871

African (AFR) AF: 0.00 AC: 0 AN: 26225

American (AMR) AF: 0.00 AC: 0 AN: 35193

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19318

East Asian (EAS) AF: 0.00 AC: 0 AN: 30157

South Asian (SAS) AF: 0.00 AC: 0 AN: 53890

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40481

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4091

European-Non Finnish (NFE) AF: 0.00000120 AC: 1 AN: 832617

Other (OTH) AF: 0.00 AC: 0 AN: 45739

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Ornithine carbamoyltransferase deficiency Benign:1

Feb 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	8.3
DANN	Benign	0.81
PhyloP100		1.3
PromoterAI		-0.046	Neutral

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: rs1602008611; hg19: chrX-38211955;