BRCA1 is a tumor suppressor gene and is responsible for DNA repairs as well as playing a role in transcription and recombination (R). 

Mutations in this gene can cause breast or ovarian cancer (R). 

Researchers have identified more than 1,800 mutations in the BRCA1 gene. Many of these mutations are associated with an increased risk of breast cancer in both men and women, as well as several other types of cancer. These mutations are present in every cell in the body and can be passed from one generation to the next. As a result, they are associated with cancers that cluster in families. However, not everyone who inherits a mutation in the BRCA1 gene will develop cancer. Other genetic, environmental, and lifestyle factors also contribute to a person's cancer risk. Most BRCA1 gene mutations lead to the production of an abnormally short version of the BRCA1 protein or prevent any protein from being made from one copy of the gene. As a result, less of this protein is available to help repair damaged DNA or fix mutations that occur in other genes. As these defects accumulate, they can trigger cells to grow and divide uncontrollably to form a tumor. ovarian cancer Many of the same BRCA1 gene mutations that increase the risk of breast cancer (described above) also increase the risk of ovarian cancer. Families with these mutations are often said to be affected by hereditary breast and ovarian cancer syndrome. Women with BRCA1 gene mutations have a 35 to 60 percent chance of developing ovarian cancer in their lifetimes, as compared with 1.6 percent in the general population. prostate cancer At least five inherited BRCA1 gene mutations have been found to increase the risk of prostate cancer. These mutations likely reduce the BRCA1 protein's ability to repair DNA, allowing potentially damaging mutations to persist in various other genes. The accumulation of damaging mutations can lead to the out-of-control cell growth and division that can cause a tumor to develop. Men who carry a BRCA1 gene mutation that increases the risk of prostate cancer may also be at increased risk for other cancers. other cancers Inherited mutations in the BRCA1 gene also increase the risk of several other types of cancer, including pancreatic cancer and colon cancer. These mutations impair the ability of the BRCA1 protein to help repair damaged DNA. As defects accumulate in DNA, they can trigger cells to grow and divide without order to form a tumor. It is not clear why different individuals with BRCA1 mutations develop cancers in different organs. Environmental factors that affect specific organs may contribute to the development of cancers at particular sites.

The BRCA1 gene provides instructions for making a protein that acts as a tumor suppressor. Tumor suppressor proteins help prevent cells from growing and dividing too rapidly or in an uncontrolled way. The BRCA1 protein is involved in repairing damaged DNA. In the nucleus of many types of normal cells, the BRCA1 protein interacts with several other proteins to mend breaks in DNA. These breaks can be caused by natural and medical radiation or other environmental exposures, and they also occur when chromosomes exchange genetic material in preparation for cell division. By helping to repair DNA, the BRCA1 protein plays a critical role in maintaining the stability of a cell's genetic information. Research suggests that the BRCA1 protein also regulates the activity of other genes and plays an essential role in embryonic development. To carry out these functions, the BRCA1 protein interacts with many other proteins, including other tumor suppressors and proteins that regulate cell division.

The following transcription factors affect gene expression:

• p53
• AP-1
• c-Jun
• Sp1
• STAT1
• NF-1
• Bach1
• p300

Tissue specificity:

Isoform 1 and isoform 3 are widely expressed. Isoform 3 is reduced or absent in several breast and ovarian cancer cell lines.

Enzyme Regulation:

The E3 ubiquitin-protein ligase activity is inhibited by phosphorylation by AURKA. Activity is increased by phosphatase treatment.

Molecular Function:

• Dna Binding
• Chromatin Binding
• Damaged Dna Binding
• Transcription Coactivator Activity
• Rna Binding
• Ubiquitin-Protein Transferase Activity
• Zinc Ion Binding
• Tubulin Binding
• Ligase Activity
• Enzyme Binding
• Ubiquitin Protein Ligase Binding
• Transcription Regulatory Region Dna Binding
• Androgen Receptor Binding

Biological Processes:

• Double-Strand Break Repair Via Homologous Recombination
• Dna Double-Strand Break Processing
• Dna Synthesis Involved In Dna Repair
• Strand Displacement
• Dna Replication
• Postreplication Repair
• Double-Strand Break Repair
• Double-Strand Break Repair Via Nonhomologous End Joining
• Regulation Of Gene Expression By Genetic Imprinting
• Transcription, Dna-Templated
• Regulation Of Transcription From Rna Polymerase Ii Promoter
• Regulation Of Transcription From Rna Polymerase Iii Promoter
• Fatty Acid Biosynthetic Process
• Apoptotic Process
• Cellular Response To Dna Damage Stimulus
• Dna Damage Response, Signal Transduction By P53 Class Mediator Resulting In Transcription Of P21 Class Mediator
• Chromosome Segregation
• Centrosome Cycle
• Brain Development
• Response To Nutrient
• Intrinsic Apoptotic Signaling Pathway In Response To Dna Damage
• Dosage Compensation By Inactivation Of X Chromosome
• Response To Ionizing Radiation
• Positive Regulation Of Vascular Endothelial Growth Factor Production
• Positive Regulation Of Gene Expression
• Protein Ubiquitination
• Protein Sumoylation
• Androgen Receptor Signaling Pathway
• Chromosome Breakage
• Positive Regulation Of Protein Ubiquitination
• G2 Dna Damage Checkpoint
• Response To Estradiol
• Negative Regulation Of Intracellular Estrogen Receptor Signaling Pathway
• Positive Regulation Of Protein Import Into Nucleus, Translocation
• Positive Regulation Of Histone Acetylation
• Negative Regulation Of Histone Acetylation
• Regulation Of Cell Proliferation
• Regulation Of Apoptotic Process
• Chordate Embryonic Development
• Response To Estrogen
• Regulation Of Dna Methylation
• Negative Regulation Of Fatty Acid Biosynthetic Process
• Positive Regulation Of Dna Repair
• Positive Regulation Of Angiogenesis
• Negative Regulation Of Transcription, Dna-Templated
• Positive Regulation Of Transcription, Dna-Templated
• Positive Regulation Of Transcription From Rna Polymerase Ii Promoter
• Negative Regulation Of Centriole Replication
• Positive Regulation Of Histone H3-K4 Methylation
• Negative Regulation Of Histone H3-K4 Methylation
• Negative Regulation Of Histone H3-K9 Methylation
• Positive Regulation Of Histone H3-K9 Methylation
• Protein Autoubiquitination
• Positive Regulation Of Histone H4-K20 Methylation
• Positive Regulation Of Cell Cycle Arrest
• Cellular Response To Tumor Necrosis Factor
• Cellular Response To Indole-3-Methanol
• Protein K6-Linked Ubiquitination
• Regulation Of Signal Transduction By P53 Class Mediator
• Negative Regulation Of Extrinsic Apoptotic Signaling Pathway Via Death Domain Receptors
• Negative Regulation Of Reactive Oxygen Species Metabolic Process
• Positive Regulation Of Histone H3-K9 Acetylation
• Positive Regulation Of Histone H4-K16 Acetylation