GENE REFERENCE / HGNC:8487
ORC1
origin recognition complex subunit 1
What does this gene do?
The ORC1 gene provides instructions for making a protein that is important in the copying of a cell's DNA before the cell divides (a process known as DNA replication). The protein produced from this gene is one of a group of proteins known as the origin recognition complex (ORC). (The complex is made up of the proteins ORC1 to ORC6, which are produced from different genes.) ORC attaches (binds) to certain regions of DNA known as origins of replication (or origins), where the process of DNA copying begins. This complex attracts additional proteins to bind to it, forming a larger group of proteins called the pre-replication complex. When the pre-replication complex is attached to the origin, replication is able to begin at that location. This tightly controlled process, called replication licensing, helps ensure that DNA replication occurs only once per cell division and is required for cells to divide.
ORC also attaches to a form of DNA called heterochromatin. Heterochromatin is densely packed DNA that contains few functional genes, but it is important for controlling gene activity and maintaining the structure of chromosomes. It is unclear what effect ORC binding has on heterochromatin.
In addition to its roles as part of ORC, the ORC1 protein is involved in the copying of cell structures called centrosomes and centrioles, which are important for the process of cell division. ORC1 blocks centrosomes and centrioles from being copied more than once, which is key to normal cell division. In addition, some research suggests that ORC1 is involved in the function of cilia, which are microscopic, finger-like projections that stick out from the surface of cells. Cilia participate in signaling pathways that transmit information within and between cells and are important for the development and function of many types of cells and tissues, including bone.
Related condition topics
MedlinePlus mentions this gene in the condition pages below. These links alone do not show that the gene causes a condition.
ClinGen reviews
We found no matching ClinGen review in the data used here. This does not rule out a link between the gene and a condition.
ClinVar records
These numbers show what has been submitted to ClinVar. They cannot tell you how likely you are to have a condition.
- Submitted alleles
- 463
- Submissions for variants in or overlapping this gene
- 721
- Submissions explicitly reporting this gene
- 694
- Alleles reported pathogenic / likely pathogenic
- 38
- VariationIDs with uncertain significance
- 202
- VariationIDs with conflicting classifications
- 27
The rows count different things: alleles, submissions or VariationIDs. Their categories can overlap, so do not add them together. Pathogenic/likely pathogenic counts exclude structural variants that merely overlap a gene. A dash in the source means “not reported,” not zero.
NCBI produces the gene-summary file each week using counts recorded at the start of the month. The numbers may differ from those on the live ClinVar website. Read the field definitions ↗
YOUR DNA FILE
Can your DNA file tell you about ORC1?
From a DNA test kit (such as 23andMe, AncestryDNA or MyHeritage). These kits check a fixed list of about 600,000 to 700,000 positions across your whole genome. ClinVar lists 38 alleles in ORC1 reported as pathogenic or likely pathogenic. A kit checks only some of these positions, and often none of them.
From whole genome sequencing (a VCF file). Sequencing reads most of your genome. Your file lists the places where your DNA differs from the reference genome. Some regions are hard to sequence, including parts of some genes that have near-identical copies elsewhere, and a VCF file does not record which positions were read well.
If a variant is not in your file, that does not mean you don’t have it.
What BioDecode checks
BioDecode compares every variant in your file with ClinVar, on your own computer. For each match, it shows the ClinVar classification, the review status and the condition it was reported for. Your file is not uploaded.
A ClinVar classification applies to one particular variant and the condition it was reported for. It does not tell you about other variants in ORC1.
BioDecode cannot fill gaps in your test, diagnose a condition or replace clinical testing.
Sources and dates
The source information on this page last changed on 2026-10-10.
HGNC Source details
Source release: Fri, 09 Oct 2026 13:40:45 GMT
Source record updated: 2023-01-20
SHA-256: e4cd9c6d7120051b80e5e61d2aeb98bd6a541ddd21f428a6eab922c11242e053
MedlinePlus Source details
Source release: Sat, 10 Oct 2026 05:16:07 GMT
Source publication: 2020-08-18
Source review: 2014-02
SHA-256: fdc8bd614310c12718379cef6569962e5d0e791cecabcc355b53a72816ac263a
ClinVar Source details
Source release: Sun, 04 Oct 2026 13:15:29 GMT
SHA-256: 126d9e5bded1d43c0380ac6684c86f9aab056d2ff2be93d743e408ed917ae558
About the library sources · Latest validated release · Record 79a47cdc896a