Genes
BRCA1
Overview
BRCA1 is a gene found in humans that plays a crucial role in preventing cancer. It produces a protein that helps repair damaged DNA, ensuring the stability of the cell's genetic material. When this gene is mutated or altered, the protein isn't made correctly and DNA damage may not be repaired properly. As a result, cells are more likely to develop additional genetic alterations that can lead to cancer. Specific inherited mutations in BRCA1 increase the risk of female breast and ovarian cancers, and they have been associated with increased risks of several additional types of cancer.
Short Overview
Conditions associated with BRCA1
BRCA1 is a gene found in humans that plays a crucial role in preventing cancer. It produces a protein that helps repair damaged DNA, ensuring the stability of the cell's genetic material. When this gene is mutated or altered, the protein isn't made correctly and DNA damage may not be repaired properly. As a result, cells are more likely to develop additional genetic alterations that can lead to cancer. Specific inherited mutations in BRCA1 increase the risk of female breast and ovarian cancers, and they have been associated with increased risks of several additional types of cancer.
Gene Function
BRCA1 is a vital gene that helps maintain the genetic stability of cells by repairing damaged DNA and regulating cell division. It produces a protein that collaborates with other proteins to mend broken DNA strands, ensuring accurate genetic information transmission during cell division. Additionally, it controls the cell growth and division process, preventing the development of cancerous cells.
Mutation and Pathology
BRCA1, a human gene, plays a significant role in the development of breast and ovarian cancers, with mutations increasing the risk of these diseases. Additionally, alterations in this gene can lead to an increased likelihood of other cancers, such as prostate and pancreatic cancer. Besides cancer susceptibility, BRCA1 also influences the timing of onset of menstruation and menopause, impacting reproductive traits.
Diagnostics
BRCA1 genetic testing is typically conducted when there's a familial history of breast or ovarian cancer, particularly if these cancers appeared early in life. The test, which can be performed on adults deemed to be at an elevated risk due to their family history, involves the analysis of a small blood or saliva sample. While a positive result does not guarantee the development of cancer, it does signify an increased risk.
Effect of Variations on the BRCA1
Variants are common variations in genes that can significantly impact the health and traits of an individual. This section shows all variants that are located on BRCA1 as well as their associated conditions, traits and drugs.
Did you know that gene anomalies are relatively common?
On average, each person has approximately 100 to 400 genes that are not normal (with different genes being affected in different people). However, usually, the matching gene on the other chromosome within the pair is normal, which helps prevent any potential negative consequences. In the broader population, the odds of someone having two copies of the same abnormal gene (and hence, a genetic disorder) are very low. However, this probability is higher for children whose parents are closely related by blood.
Dr. Wallerstorfer
Conditions caused and influenced by BRCA1
Genetic abnormalities can significantly influence the likelihood of developing a certain condition, either increasing or decreasing the risk. These mutations can alter gene function, which may result in protein malfunction or a lack of protein production. However, even if a genetic mutation increases the risk, it doesn't necessarily mean the condition will develop as environmental and lifestyle factors also play a role.
Did you know the difference between mutations, genetic variations, variants and haplotypes?
Mutations are random changes in the DNA and genetic variations are differences in the DNA among people. Variants are tiny changes in just one piece of the DNA while haplotypes are groups of these changes that usually come together.
Dr. Wallerstorfer
Traits caused and influenced by BRCA1
Abnormalities in genes can also have a significant impact on an individual's traits, or physical characteristics. These genetic mutations can affect the way certain traits are expressed by modifying the function of the related genes. However, the manifestation of these traits isn't determined by genetics alone. It's also influenced by a combination of environmental factors and interactions with other genes. Thus, while a gene mutation can potentially influence a trait, it doesn't necessarily dictate its final expression.
Did you know that Genes vary substantially in size?
In the human genome, there are approximately 21,000 protein-coding genes. Notably, 17,000 of these genes contain only a single variant. However, a small fraction, around 6%, contain more than 50 variants. One gene, CSMD1, stands out significantly with a total of 1008 variants. In terms of size, CSMD1 spans over 818 kilobases, making it considerably larger than TDF, which is one of the smallest genes in the human genome at just 35 kilobases.
Dr. Wallerstorfer
Variants located on BRCA1
A genetic code of a gene usually has many differences in individual genetic letters or tiny pices of the DNA.
Did you know variants may affect drugs?
Variants can influence how our body reacts to certain drugs. The presence of specific variants can increase or decrease the efficiency and effectiveness of a drug, impacting how well it works inside our system. Additionally, certain variants can heighten or lessen the toxicity of a drug, thereby affecting the risk of unwanted side effects. They can also alter how a drug is metabolized, which influences the appropriate dosage one should receive.
Dr. Wallerstorfer
Pharmacogenetics
Variants can significantly influence how our body processes and reacts to drugs. The presence of specific variants can determine the efficiency and effectiveness of a medication, influencing its performance within our system. Additionally, certain variants can modify the drug's toxicity, thereby affecting the likelihood of unwanted side effects. They can also impact how a drug is metabolized, which in turn determines the ideal dosage one should receive. Every individual's response to medication can vary, largely dictated by their genetic makeup. Variations in genes can influence the functions of enzymes, transporters, receptors, and other proteins that interact with drugs. For example, certain genetic variants can alter an enzyme's function, causing it to metabolize a drug too quickly or too slowly. Such variations can either render a treatment ineffective or heighten the risk of side effects.
Gene Function & Mechanism
BRCA1, a human gene, plays a crucial role in maintaining the stability of a cell's genetic information. It is involved in repairing damaged DNA, regulating cell division, and controlling the life cycle of a cell. The gene produces a protein that interacts with numerous other proteins to carry out these functions. The following points provide a deeper understanding of the specific roles and mechanisms associated with BRCA1.
DNA Repair: The gene is instrumental in the repair of DNA double-strand breaks, a type of DNA damage that can lead to genetic instability if not corrected. The protein it produces teams up with other proteins to mend the broken DNA strands, ensuring the accurate transmission of genetic information during cell division.
Cell Cycle Regulation: The gene also plays a role in regulating the cell cycle. It helps control the process by which cells grow and divide, ensuring that cell division occurs correctly and at the right time. This regulation helps prevent the development of cancerous cells.
Protein Interaction: The protein produced by the gene interacts with many other proteins within a cell. These interactions enable the protein to carry out its functions in DNA repair and cell cycle regulation. The protein's ability to interact with others is crucial for maintaining genetic stability.
Gene expression
BRCA1 is a gene that our bodies use as a blueprint to make a protein with a vital role in repairing damaged DNA. The process begins when the DNA in our cells is "read" or transcribed into a molecule called messenger RNA (mRNA). This mRNA then serves as a template for building the BRCA1 protein in a process called translation. The amount of BRCA1 protein produced can vary, influenced by factors such as stress, age, and overall health. If the BRCA1 gene is altered or mutated, it can lead to the production of a faulty protein, which may increase the risk of developing certain types of cancer.
Prompoters and Inhibitors
BRCA1, a crucial gene in our bodies, is regulated by certain promoters and inhibitors. Promoters, like E2F1 and p53, are like the gas pedal in a car, they help speed up the activity of BRCA1. On the other hand, inhibitors such as Id4 and HSP90, act like the brakes, slowing down BRCA1's activity. This balance between promoters and inhibitors ensures that BRCA1 functions properly, helping to repair damaged DNA and maintain the stability of our genetic material. Any disruption in this balance can lead to problems, including an increased risk of certain types of cancer.
Protein Structure
BRCA1 proteins are like a Swiss army knife, with different parts, or domains, each having a unique function. The first part, the RING domain, is like a foreman, directing other proteins to repair damaged DNA. The BRCT domains, at the other end, are like a pair of hands, holding onto other proteins to help fix DNA. In the middle, there's the coiled-coil domain, which is like a communication hub, helping the protein interact with others. Lastly, the serine cluster domain acts like a switch, turning on the protein's DNA repair function when needed.
Protein Interactions
The proteins produced by the BRCA1 gene work like a team of construction workers, interacting with many other proteins to maintain the stability of a cell's genetic information. They play a crucial role in repairing damaged DNA, a complex process that involves several other proteins. When DNA damage is detected, these proteins act like an emergency response team, rushing to the site to fix the problem. They also help control the cell's life cycle, ensuring it grows and divides at the right time. In essence, the BRCA1 proteins are key players in a cell's defense system, working with other proteins to keep the cell healthy and functioning properly.
Similar Genes
Similar to BRCA1, genes such as PALB2, TP53, and PTEN also play a crucial role in maintaining the stability of a cell's genetic information. These genes, like BRCA1, are involved in repairing damaged DNA, a process vital for preventing the development of cancer. Mutations in these genes can lead to an increased risk of certain types of cancer, including breast and ovarian cancer. In essence, these genes act as the body's own defense system against cancer, and when they don't function properly, the risk of cancer can increase. Therefore, understanding these genes and their functions can provide valuable insights into cancer prevention and treatment.
Gene interaction
The BRCA1 gene does not work in isolation but interacts with several other genes in the body. These interactions are crucial for the gene's function in maintaining the stability of a cell's genetic information. The following are some of the key genes that BRCA1 interacts with and the nature of these interactions.
RAD51: This is a gene that BRCA1 interacts with to repair DNA. When DNA damage occurs, BRCA1 helps recruit this gene to the site of damage. This collaboration is essential for the repair of DNA double-strand breaks, a severe form of DNA damage.
BARD1: This is another gene that interacts closely with BRCA1. The proteins produced by these two genes combine to form a complex. This complex plays a significant role in repairing damaged DNA and regulating cell division.
PALB2: This is a partner gene of BRCA1. It acts as a bridge between BRCA1 and another gene involved in DNA repair. This interaction is crucial for the proper functioning of the DNA repair process.
Did you know that proteins and genes can have the same name?
In most cases, a gene codes for a specific protein, meaning the primary function of a gene is to provide instructions for producing a protein. Due to this intimate relationship, scientists often use the same name for both the gene and the protein it codes for.
Dr. Wallerstorfer
Diagnostics
BRCA1 is typically diagnosed through a genetic test, which involves analyzing a small sample of blood or saliva. This test is often recommended when there is a family history of breast or ovarian cancer, especially if these cancers developed at a young age. The timing of the test varies, but it is usually offered to adults who are at a higher risk due to their family history. The results can take a few weeks to come back from the laboratory. It's important to note that a positive result doesn't mean cancer is inevitable, but it does indicate a higher risk.
Living with
Variations in the BRCA1 gene can significantly increase the risk of developing breast and ovarian cancer in carriers. These variations can also increase the likelihood of other cancers, such as prostate and pancreatic cancer. The risk is particularly high for women, with about 72% of those with a BRCA1 mutation developing breast cancer by the age of 80. Genetic testing can identify these variations, allowing carriers to make informed decisions about preventive measures, such as increased screening or preventive surgeries. However, it's important to note that not everyone with a BRCA1 variation will develop cancer; many factors, including lifestyle and environment, can influence this risk.
Did you know genetic tests are affordable?
Genetic tests, once regarded as a luxury due to their high costs, have become significantly more affordable. This change has been made possible through advancements in technology and increased competition in the market. Now, anyone curious about their genetic makeup and potential health risks can access this information at an affordable price. This development provides unprecedented insights into individual genetics.
Dr. Wallerstorfer
When to test BRCA1
A test for BRCA1, a gene associated with breast and ovarian cancer, is typically conducted under certain circumstances. These include having a personal or family history of breast or ovarian cancer, particularly if diagnosed at a young age or if multiple family members have had these cancers. Additionally, individuals of certain ethnic backgrounds, such as Ashkenazi Jewish descent, where these mutations are more common, may also be recommended for testing.
Did you know the common mutations?
Mutations in the BRCA1 gene are relatively rare, affecting about 1 in 400 to 1 in 800 people in the general population. However, the frequency can vary significantly among different ethnic and geographic populations. For instance, certain groups, such as Ashkenazi Jews, have a higher prevalence, with about 1 in 40 individuals carrying a BRCA1 mutation.
Dr. Wallerstorfer
Genes tested together with
Genetic testing often involves more than just one gene. When testing for BRCA1, a gene associated with breast and ovarian cancer, other genes are usually tested simultaneously. These genes can also be linked to an increased risk of certain types of cancer. The following genes are commonly tested alongside BRCA1:
BRCA2: This is another gene that, when mutated, can increase the risk of breast and ovarian cancer. It is often tested together with BRCA1 to provide a more comprehensive understanding of a person's genetic risk.
PALB2: This is a gene that works with BRCA2 to repair damaged DNA and stop tumor growth. Mutations in this gene can also increase the risk of breast cancer, making it a common addition to BRCA testing.
ATM: This is a gene that helps control cell division. Mutations in this gene can lead to cells dividing in an uncontrolled way, which can increase the risk of certain types of cancer, including breast cancer.
CHEK2: This is a gene that produces a protein involved in the repair of damaged DNA. A mutation in this gene can increase the risk of developing various types of cancer, including breast and colon cancer.
Each of these genes can contribute to an individual's overall risk profile for developing breast and ovarian cancer, and understanding these risks can be crucial in the management of one's health. It is important to consult a healthcare professional to discuss any concerns related to genetic testing and cancer risk.
Did you know that pharmacogenomics is a thing?
Genetic testing can offer insights into how your body metabolizes specific medications, leading to more personalized and effective treatment plans. The genetic tests designed for this purpose are known as pharmacogenomic tests. Pharmacogenomics is the study of how genes influence an individual's response to drugs.
Dr. Wallerstorfer
History
The discovery of BRCA1, a human gene associated with breast cancer, dates back to the early 1990s. Scientists had long suspected that some forms of breast cancer were hereditary, but it wasn't until 1990 that the first major breakthrough occurred. A team led by Mary-Claire King demonstrated that a single gene on chromosome 17 was responsible for many breast and ovarian cancers. This gene was later named BRCA1. In 1994, after four years of intensive research, Mark Skolnick and his team at Myriad Genetics were able to identify and isolate BRCA1. This was a significant milestone in cancer research as it opened up new avenues for understanding the genetic basis of breast and ovarian cancer. Since then, BRCA1 has been the subject of numerous studies, leading to improved genetic testing and targeted treatments for those carrying mutations in this gene. Today, BRCA1 continues to be a key focus in the ongoing battle against hereditary cancers.