BRCA1 vs BRCA2: Understanding Genetic Cancer Risks
BRCA1 and BRCA2 are the genes linked to an increased risk of ovarian and breast cancer.
These genes usually help in preventing cancer by repairing damaged DNA.
But when mutated, these genes make a person more prone to various types of cancer.
So, it is important to understand the difference between these two genes and assess the cancer risk.
According to National Cancer Institute, BRCA1 and BRCA2 mutation prevalence is about 0.2% to 0.3% in the general population.
In this article, we will discuss BRCA1 vs BRCA2 on the basis of the increased risk of cancer and mutation.
A quick review: BRCA1 vs. BRCA2
| BRCA1 Mutation | BRCA2 Mutation | |
|---|---|---|
| Associated Cancers | Breast, ovarian, fallopian tube, peritoneal | Breast, ovarian, pancreatic, prostate |
| Breast Cancer Risk | Increased risk of triple-negative breast cancer | Increased risk of breast cancer |
| Ovarian Cancer Risk | Increased risk of ovarian, fallopian tube, and peritoneal cancers | Increased risk of ovarian cancer |
| Other Cancer Risks | No increased risk of pancreatic or prostate cancer | Increased risk of pancreatic and prostate cancers |
| Inheritance | Autosomal dominant | Autosomal dominant |
What is BRCA1 and BRCA2
BRCA1 and BRCA2 are two Breast Cancer genes generally pronounced as BRACA.
These are short names given to the terms BReast CAncer susceptibility gene 1 and BReast CAncer susceptibility gene 2.
Both genes are present in everyone but can increase your chances of breast and ovarian cancer if mutated.
These genes are inherited either from your mother or your father.
However, not everyone who inherits BRCA1 or BRCA2 mutation will get cancer.
BRCA1 and BRCA2 are tumor suppressor genes because they help repair DNA damage and maintain genomic stability.
Difference between BRCA1 and BRCA2
BRCA1 and 2 are two completely different genes, even though mutation on either BRCA1 or BRCA2 cause cancer.
BRCA1 was first discovered in 1990 on chromosome 17, and BRCA2 was found on chromosome 13.
The main difference is the type of cancer associated with the genes and their presence in specific populations.
BRCA1 mutation increases the risk of Triple-Negative Breast Cancer and has a higher risk of Ovarian Cancer.
On the other hand, BRCA2 is commonly associated with breast, ovarian, pancreatic, and prostate cancer.
The prevalence of BRCA1 mutation is higher in the Ashkenazi and the Jewish population.
While BRCA2 mutations are prevalent in Iceland, Netherlands, and Norway individuals.
Associated cancer risks
As per a study published by the National Center of Biotechnology Information explains the risk of hereditary Breast and Ovarian Cancer due to BRCA1 and BRCA2 mutations.
The risk of cancer in individuals with mutations compared to the general population is as follows:
| General Population Risk | Increased risk | ||
| BRCA1 | BRCA2 | ||
| Breast Cancer | 12% | 55%-72% by the age of 70 years | 45%-69% |
| Ovarian Cancer | 1%-2% | 39%-44% | 11%-17% |
| Male Breast Cancer | 0.1% | 1%-2% | 6%-8% |
| Prostate Cancer | 6% by the age of 69 years | 21% by the age of 75 years29% by the age of 85 years | 27% by the age of 75 years60% by the age of 85 years |
| Pancreatic Cancer | 0.5% | 1%-3% | 3%-5% by the age of 70 years |
| Melanoma (cutaneous & ocular) | 1.6% | Higher risk | |
Comparing the risk
The BRCA1 and BRCA2 gene mutations increase the risk of developing certain cancers, including breast and ovarian cancer.
However, as stated above, BRCA1 is associated with higher risks of Triple-Negative Breast Cancer, a more aggressive cancer.
Triple-Negative Breast Cancer is hard to treat than other types of Breast Cancer.
By the age of 70, women with BRCA1 mutations have a higher chance of getting Breast Cancer than BRCA2.
Cancer.net states that individuals with BRCA2 mutation have a 7% risk of developing Male Breast Cancer.
Whereas mutation in the BRCA1 gene has a 1% risk of developing Male Breast Cancer.
Both genes, when mutated, can cause severe health problems such as ovarian, prostate, uterine, cervical cancer, and melanoma.
BRCA1 and BRCA2 genetic testing
The BRCA genetic test uses a sample of your saliva, blood, or saliva from inside your cheeks.
These test checks for any changes in your BRCA1 and BRCA2 genes.
Changes in your genes are known as mutated genes or gene variants, and not all are harmful.
Some of the gene tests are as follows:
- Blood test: A healthcare professional will take a blood sample from your veins using a needle. This test generally takes less than five minutes
- Saliva test: Your saliva will be collected in a small jar, or you can also use a cotton pad to soak up some saliva
- Cheek swab: A healthcare professional will wipe the inside of your cheeks using a cotton swab or pad. You can also do this yourself
You may receive your test results within two to four weeks after your tests.
The BRCA1 and BRCA2 tests can range from $300 to $5000 or more, depending on lab fees and other criteria.
Generally, various private insurance companies cover BRCA gene testing for individuals who meet their criteria.
Takeaway
In conclusion, BRCA1 and BRCA2 gene mutations are significant concerns when considering cancer risks.
BRCA1 mutations have a higher risk of developing Triple-Negative Breast Cancer, making it more problematic.
Also, women with BRCA1 mutations face a greater chance of developing breast cancer by the age of 70 compared to BRCA2 mutations.
BRCA2 mutation has a higher risk of male breast cancer than BRCA1 mutations.
Understanding these differences is crucial for assessing individual risks and taking appropriate preventive measures.
Frequently Asked Questions
Which is more aggressive, BRCA1 or BRCA2?
BRCA1 gene mutation is considered more aggressive than BRCA2 mutations. BRCA1 is associated with a higher risk of developing aggressive forms of breast cancer, such as triple-negative breast cancer.
Is it better to be BRCA positive or negative?
It is generally considered better to be BRCA negative, as it indicates a lower chance of having mutations in the BRCA1 or BRCA2 genes. The mutation of these genes is associated with increased risks of breast and ovarian cancer.
Are BRCA1 and BRCA2 hereditary?
Yes, BRCA1 and BRCA2 are hereditary. It means they can be passed down from parents to their children. Having a family history of these mutations increases the risk of inheriting them.
Are BRCA1 and BRCA2 oncogenes?
BRCA1 and BRCA2 are tumor suppressor genes. They release proteins that help in repairing damaged DNA. So, these genes can not be oncogenes but tumor suppressor genes that can become defective and cause cancer.
Are BRCA1 and BRCA2 inherited from the mother or father?
BRCA1 and BRCA2 gene mutations can be inherited from your mother or father. Each child of a parent who carries any mutation in one of these genes has a 50% chance (or 1 in 2 chance) of inheriting the mutation. However, everyone who inherits a BRCA1 or BRCA2 mutation will not get breast or ovarian cancer.
WowRx uses only high-quality sources while writing our articles. Please read our content information policy to know more about how we keep our content reliable and trustworthy.
