rs61753389

Positions:

• chr1-52374887-C-G
• chr1-52374887-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_004153.4(ORC1):​c.2314G>C​(p.Val772Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V772I) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: ORC1 NM_004153.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.02

Genes affected

ORC1 (HGNC:8487): (origin recognition complex subunit 1) The origin recognition complex (ORC) is a highly conserved six subunits 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. The protein encoded by this gene is the largest subunit of the ORC complex. While other ORC subunits are stable throughout the cell cycle, the levels of this protein vary during the cell cycle, which has been shown to be controlled by ubiquitin-mediated proteolysis after initiation of DNA replication. This protein is found to be selectively phosphorylated during mitosis. It is also reported to interact with MYST histone acetyltransferase 2 (MyST2/HBO1), a protein involved in control of transcription silencing. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.048641115).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ORC1	NM_004153.4	c.2314G>C	p.Val772Leu	missense_variant	16/17	ENST00000371568.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ORC1	ENST00000371568.8	c.2314G>C	p.Val772Leu	missense_variant	16/17	1	NM_004153.4	P1
ORC1	ENST00000371566.1	c.2314G>C	p.Val772Leu	missense_variant	16/17	1		P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

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

Jul 19, 2022

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 772 of the ORC1 protein (p.Val772Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ORC1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1395422). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The leucine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Benign	-0.39	T
BayesDel_noAF	Benign	-0.79
CADD	Benign	1.0
DANN	Benign	0.66
DEOGEN2	Benign	0.0076	T;T
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.4
FATHMM_MKL	Benign	0.11	N
M_CAP	Benign	0.0035	T
MetaRNN	Benign	0.049	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.87	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-0.14	N;N
REVEL	Benign	0.043
Sift	Benign	0.78	T;T
Sift4G	Benign	1.0	T;T
Polyphen		0.0	B;B
Vest4		0.11
MutPred		0.41		Gain of catalytic residue at V772 (P = 0.0216);Gain of catalytic residue at V772 (P = 0.0216);
MVP		0.21
MPC		0.15
ClinPred		0.082	T
GERP RS		-0.62
Varity_R		0.11
gMVP		0.13

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-52840559;