What is the risk of developing cancer due to genetic inheritance?

“Cancer” is the name given to a series of related diseases in which an uncontrolled process of cell division is observed in some part of the body.

Of course, this clinical definition does not do justice to the pain and suffering that these pathologies generate in modern society.

Cancer goes far beyond a terminological conglomerate, as we all know someone who has. suffered, and certainly, we present a not inconsiderable risk of facing him at some point in our life. our lives. Unfortunately, we are facing one of the main causes of death in the world, since cancers of the respiratory tract occupy the eighth place in terms of global deaths are concerned, while cancer overall tops second place in high-income countries, just behind diseases cardiovascular.

As bleak and unpleasant as this topic can be, facing the enemy and getting to know them is the first step in taking them down. Therefore, on this occasion we explore the risk of developing cancer due to genetic inheritance, among other issues related to this group of diseases that are so difficult to address. Go for it.

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Risk of developing cancer due to genetic inheritance: a family matter?

Understanding the magnitude of cancer in society is difficult if we do not expose ourselves to certain facts and figures. The National Cancer Institute (NIH) gives us the following information:

• Every year 439 cases of cancer are diagnosed for every 100,000 men and women. The mortality of this group of pathologies stands at 163 deaths per 100,000 inhabitants per year.
• The most common cancers are breast, lung, prostate and colon, among others.
• In the United States alone, it is estimated that almost 2 million new cases are diagnosed each year.

Things get worse if we see these figures as something cumulative and not isolated. Yes, almost 500 cases of cancer are diagnosed every year for every 100,000 people, that doesn't sound like much. The key is that the probabilities are annual, that is, cumulative throughout the life of the individual.

Thus, an American male is estimated to have an 11% chance of developing a colon cancer in your lifetime (absolute risk), not counting the odds for the rest of variants. The scariest figure of all is this: nearly 40% of the human population will be diagnosed with cancer at some point in their lives.

These data must be contextualized, since it is certainly not the same to detect a neoplasm in a 90-year-old as a malignant tumor in a 30-year-old. Numerical figures should be dissected by age groups, risk factors, and other considerations. In addition, in 2016 there were more than 15 million cancer survivors in the United States, so this diagnosis is less and less directly correlated with death. In short: no need to panic.

Despite this call for calm and necessary appreciation for the fight against hypochondrism, we cannot deny that these data show that cancer is here to stay in our society. Thus, exploring factors such as the risk of developing cancer due to genetic inheritance is essential. We show you what is known so far.

question of genes

First of all, it is necessary differentiate a hereditary familial cancer syndrome from an environmental issue. If several people smoke in a family nucleus, it is not a surprise for anyone that more than one of the members can develop lung cancer, since up to 90% of deaths from these neoplasms are related to the consumption of tobacco. The same happens with obesity, for example, which can promote the appearance of these types of cancer.

If a family is in an area full of pollutants, works together in an unhealthy environment, has habits inappropriate general rules and many other factors, it is natural to think that its members will have a better chance of developing a cancer. This does not necessarily correspond to a genetic predisposition, but rather an environmental or behavioral one.

Once this issue has been clarified, it is necessary to clarify that there are hereditary cancer syndromes. It is estimated that 5-10% of cancer processes are associated with heritable genetic factors, since researchers have associated mutations in more than 50 specific genes that predispose carriers to suffer from this group of diseases.

Once the term “mutation” has been introduced, it is essential that we frame it within the etiology of cancer. As we have already said before, the malignant tumor process is due to a cellular mutation, by which these Cells divide abnormally quickly and do not meet cell death and proliferation times typical. This gives rise to the dreaded tumor, a mass of abnormal tissue that does not respond to any biological functionality. Thus, the genetic mutations that promote this situation can be inherited or acquired:

Mutations of a hereditary nature are present in the egg or sperm that form the child. As all the cells of the fetus come from a single primordial cell, we can affirm that this kind of mutation is found in each cell of the individual (including eggs and sperm), so it can be transmitted to the following generations.

On the other hand we have somatic or acquired mutations, which do not come from one of the parents but occur throughout the individual's life time. In this case, the mutation originates in a cell of a specific tissue, and the entire descendant cell line will present, but will not be present in body cells already formed or dividing independently of the carcinogenic. Most cancers are caused by these types of mutations.

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A specific case: breast cancer

In the case of the risk of developing cancer due to genetic inheritance, we can say that many familial cancer syndromes are caused by hereditary mutations in tumor suppressor genes. These genes are of essential importance, since control cell growth, correct replication errors, and indicate when cells should die.

We may be reductionists, but we are going to explain this conglomerate in the most friendly way possible: we have two copies of each gene (one from the father and one from the mother), so inheriting an abnormal gene should not be a problem as long as the other is functional.

Things get complicated when the second copy of the inherited gene stops working (due to an acquired mutation, perhaps, or because the other parent also has the defective gene), since in this case, when the two copies are "wrong", the tumor suppressor gene can lose its functionality. Naturally, this translates into a higher chance of getting cancer.

An exemplary case of this event is breast cancer, since it has been irrefutably demonstrated that 5% of cases are related to genes of autosomal dominant inheritance. For example, mutations in certain genes such as BRCA1 and BRCA2 are clearly correlated with cancerous processes in the breast and ovaries. Since these genes are involved in the process of tumor suppression and genetic repair, it is not surprising. that its inactivation or defective regulation increases the chances of suffering from certain types of tumors malignant

Summary

Is there a risk of developing cancer due to genetic inheritance? Yes, as we have said, 5 to 10% of cancers are related to hereditary factors. Should I worry about getting cancer if a close relative has had it? Unless the doctor tells you to carry out tests associated with the genetic field, no.

It is only necessary to see these data to discard any trace of hypochondrism: 5% of cancers They occur due to genetic predisposition, 10% due to working conditions, and the remaining 80-90% due to work habits. life. Although it is a statement that requires multiple meanings, we prefer that this be the general message.

In most cases, cancer does not magically appear. factors such as smoking, alcoholism or obesity present a clear correlation with this group of diseases. Therefore, our lifestyle is the key to survival, beyond any genetic conditioning.

Bibliographic references:

• Caldes, T. (2006). Hereditary cancer: genetic foundations. Psycho-oncology, 2(2), 183-96.
• Cancer genetics, Clinic Barcelona. Collected on September 30 in https://www.clinicbarcelona.org/asistencia/enfermedades/cancer/genetica-del-cancer#:~:text=El%20c%C3%A1ncer%20es%20una%20enfermedad, the%20that%20is%C3%A1n%20the%20genes.
• Cancer Genetics, National Cancer Institute (NIH). Collected on September 30 in https://www.cancer.gov/espanol/cancer/causas-prevencion/genetica#2
• Cancer risk: what the numbers mean, Mayoclinic.org. Collected on September 30 in https://www.mayoclinic.org/es-es/diseases-conditions/cancer/in-depth/cancer/art-20044092#:~:text=El%20riesgo%20absoluto%20es%20de, approximately%20a%2011%20per%20percent.
• Cancer Syndromes in Families, American Cancer Society. Collected on September 30 in https://www.cancer.org/es/cancer/causas-del-cancer/genetica/sindromes-de-cancer-familiar.html