2-147935626-ACT-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_181741.4(ORC4):c.1193_1194del(p.Glu398ValfsTer10) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,168 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: ORC4 NM_181741.4 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.50

Genes affected

ORC4 (HGNC:8490): (origin recognition complex subunit 4) The origin recognition complex (ORC) is a highly conserved six subunit protein complex essential for the initiation of the DNA replication in eukaryotic cells. Studies in yeast demonstrated that ORC binds specifically to origins of replication and serves as a platform for the assembly of additional initiation factors such as Cdc6 and Mcm proteins. This gene encodes a subunit of the ORC complex. Several alternatively spliced transcript variants, some of which encode the same protein, have been reported for this gene. [provided by RefSeq, Oct 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.09 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ORC4	NM_181741.4	c.1193_1194del	p.Glu398ValfsTer10	frameshift_variant	14/14	ENST00000392857.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ORC4	ENST00000392857.10	c.1193_1194del	p.Glu398ValfsTer10	frameshift_variant	14/14	1	NM_181741.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000797 AC: 2 AN: 250874 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135562

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

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: 0.00000342 AC: 5 AN: 1461168 Hom.: 0 AF XY: 0.00000275 AC XY: 2 AN XY: 726908

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000671

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 05, 2023

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant has not been reported in the literature in individuals affected with ORC4-related conditions. This variant is present in population databases (rs750693936, gnomAD 0.006%). This sequence change creates a premature translational stop signal (p.Glu398Valfs*10) in the ORC4 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 39 amino acid(s) of the ORC4 protein. -

Computational scores

Source: dbNSFP v4.3

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: rs750693936; hg19: chr2-148693195;