Article: What “The Truth About Cancer” got wrong about BRCA mutations and cancer

Contents

Epigenics

TACGQ video

The video’s argument centers on epigenetics, which is explained as something that acts on your genes.  The analogy given in the video is, “Your genetics is your software and something has to open it up and read it.” Further discussion states how epigenetics allows you to turn your genes on and off.

Science

Epigenetics is an active area of biology research that studies how genes can be switched “on” and “off” by external factors. Genes are the instructions used by your body’s cells to make proteins and other molecules that carry out cellular work. Cells have many ways to control genes (or turn them on and off)—it is neither efficient or desirable to have every possible protein made all of the time.  If an external factor prevents the gene from making the protein, one can say the gene is “turned off.” However, this does not apply to deleterious BRCA gene mutations because the issue is not whether or not the gene is “turned on or off.” Rather, the issue is that these mutations are incorrect instructions.

Regardless of epigenetics, mutated genes CANNOT make a proper protein because the instructions to make it are wrong from the start. Turning a mutated BRCA gene “on” or “off” does not affect cancer risk. If a light bulb has no conductive wires, flipping the switch will not turn the light on; conversely, switching it off will not work either—nothing will change because the light bulb remains damaged and lacks the necessary components to function. That is why an epigenetic external factor cannot turn a mutated BRCA gene on and off—the gene is already broken and no external influence can manipulate it so that it works again.

TACGQ video:

Claiming that doctors would like you to believe that cancer is genetic and arises from a genetic predisposition, the video states, “Let’s say that your body and your genetics is the computer. That is the hardware. The epigenetics is the software. The software runs the hardware. What we need to do is not dwell on the genetics, but the epigenetics.” But this claim is incorrect and untrue.

Science:

All cancer is considered genetic because It is caused by damage to genes that are either inherited or occur with age. When the genes that control cell growth and division are damaged, cells no longer have instructions to control their growth, and these errors sometimes cause the cells to become cancerous.  If you apply the video’s analogy to people with BRCA mutations, the software cannot control the hardware if the hardware is already broken.

How genes work
 

TACGQ video:

The video also says that genes do not control life. It states that you can activate and deactivate genes, and that if you deactivate your genes with a healthy lifestyle, you do not get cancer.

Science:

Our genes do control life. Our environment, including lifestyle, can affect when genes are turned on and off, but ultimately it is the combination of our genetics AND our environment that have ultimate influence. External environmental factors affect our genes, but cannot change a malfunctioning gene into one that functions properly. While it is important to live a healthy lifestyle, that does not automatically deactivate “bad” genes or activate “good ones.”

Epigenics and BRCA mutations

TACGQ video:

The video says that our epigenetic influences turn genes on and off, so you don’t have to worry about the genes you inherit from your parents.

Science:

Inherited BRCA mutations are present in every cell of the body and cannot be turned on and off by environmental factors.

TACGQ video:

The video claims that the way women live their lives will alter their BRCA mutations.

Science:

Drinking alcohol and obesity are risk factors for breast cancer, while exercise is a protective factor, both for people who do and do not have BRCA mutations. Although unhealthy habits may increase risk, healthy habits do not eliminate anyone’s risk of breast cancer. Avoiding alcohol and getting enough exercise does not affect the BRCA mutation itself, and currently, we have no convincing evidence that diet, exercise, or other lifestyle choices will significantly change the cancer risk for a person with a BRCA mutation.  However, healthy lifestyle choices can improve quality of life for cancer survivors and those at high risk for cancer.

Inherited mutations

TACGQ Video:

The video avoids answering the question about whether BRCA mutations can be inherited, and instead talks about how we can turn genes on and off depending on what we eat and how well we sleep.

Science:

BRCA mutations are inherited. Fathers and mothers who carry a BRCA mutation have a 50 percent chance of passing it along to each of their children.

It is important to note that none of the people who provided information for the video are medical oncologists. Ultimately, “The Truth About Cancer: A Global Quest” is full of misleading information that is not grounded in science. This type of misinformation is dangerous, because it may lead high-risk women to drawing incorrect and dangerous conclusions about their ability to prevent cancer through healthy lifestyle alone.

A healthy lifestyle, diet, and exercises are beneficial to everyone—cancer survivors, previvors, and those of average cancer risk.  However, the cancer risk for people who have mutations in BRCA or other genes associated with hereditary cancer is greatly increased. National guidelines outline screening and risk management options.  If you have a mutation, or you are concerned that your cancer or the cancer in your family is hereditary, please discuss your risk management options with your health care provider. 

References

The Truth About Cancer website (note: access to the documentary requires registration). 

Posted 11/10/15