Is Skin Cancer Genetic? What to Do If Skin Cancer Runs in Your Family
These days, asking if something is genetic has become second nature (if you are in science, that is). The field of genetics has blossomed over the past few years to something incredible. We have found out things about our genetic blueprint that has not only helped us understand molecular biology on a deeper level, but we have also begun asking many more questions. Is skin cancer genetic? What are the risk factors? Is it caused by skin aging? Is it related to other skin diseases?
Like with ovarian cancer, lung cancer, pancreatic cancer, and colon cancer, is skin cancer genetic? And, if it is, does it run in your family and what should you do about it? In order to address these questions properly, a little bit of a cancer background, as well as skin cancer, in particular, would be appropriate
When you think of the word cancer, several things come to mind, such as cell death, accumulation of faulty cells, faulty cell division mechanisms, to name a few. (And even if these things do not come to mind, hopefully, things will be a bit clearer by the end of the post.) You see, cancer is an umbrella term for several types of cancer conditions that are all different depending on the region of the body they affect as well as a few other factors. Recent bio engineering advancements have helped us realize that cancer can be genetic, meaning that there are mutations that cause problems in cellular mechanisms that ultimately lead to tumors and/or cancers. For example, there are mutations that result in cells not diving properly. There are genetic mutations that cause these cells to keep accumulating without the body realizing that one of its very own processes is faulty. This accumulation leads to a mass of cells in one place, which is also a tumor.
Skin cancer is one type of cancer that affects the skin, as the name implies, and it is estimated that there are more than 100 kinds of skin cancer. It is also estimated that nearly half of all Americans over the age of 65 will have this type of cancer at least once in their lifetimes. The two most common kinds of skin cancer, also referred to as non-melanoma skin cancers (affecting the skin and not the pigment-producing cells, or melanocytes), are called basal cell carcinoma (most common skin cancer type, affects the top layer of the skin and typically does not spread) and squamous cell carcinoma (affects flat, plate-like cells in the top layer of skin, second most common skin cancer, can spread if left untreated). These are typically the result of too much exposure to the sun.
The more severe type of cancer, the kind that affects the melanocytes, is called invasive, cutaneous melanoma. Also referred to as malignant melanoma, it is a type of cancer that begins in the melanocytes. As mentioned previously, melanocytes are cells that produce pigment, also called melanin. While the majority of cases of this type of cancer are caused by too much exposure to ultraviolet radiation, a fancy word for “sun exposure,” about 5–10% of these have been found to be genetic. More specifically, one of these kinds of hereditary cancers is called the familial atypical mole-melanoma syndrome (FAM-M syndrome) that is thought to be caused by mutations in the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene that is located on chromosome 9. (For the purposes of this post, let us not get into the CDKN2A mechanism as it is rather a lengthy process of explaining.) In short, this genetic mutation is referred to as a p16 mutation (it is one of those mutations that was mentioned earlier that causes uncontrolled cell growth), and it is passed on in an autosomal dominant way. This is just a fancy, scientific way of saying that parents who have the mutation have a 1 in 2 chance of passing it on to their children, regardless of their gender. Individuals who are carriers of that mutation are at a much higher risk for developing a kind of melanoma (as well as potentially developing pancreatic cancer).
As many as 40% of inherited cases of melanoma are associated with the p16 mutation, which is why it is highly recommended to get tested for it if is known that skin cancer runs in the family.
A few other genetic markers—or gene mutations that point to potential skin cancer risks—have been found. An increased risk for basal cell carcinoma, for example, has been associated with mutations in the Patched (PTCH1) and (PTCH2) genes. Other genes that have been found in association with skin cancer include the cyclin-dependent kinase 4 and 6 (CDK4 and CDK6), the ubiquitin carboxyl-terminal hydrolase (BAP1) and the breast cancer (BRCA2) genes. In other words, mutations in each of these genes have been associated with an increased risk for skin cancer.
So, what to do if skin cancer runs in your family? First, get tested for all of the mutations that have been associated with skin cancer. This includes all the aforementioned genes as well as the p16 mutations to be really sure about your genetic predisposition as your chances of developing a skin cancer are definitely much higher if you are a p16 carrier. Other things to do are avoiding sun exposure as much as possible. Now, this does not mean that you should avoid the sun at all costs and avoid daylight. You are not a vampire. This means that you should wear sunscreen and avoid prolonged direct exposure to sunlight to a point of burning. Most of us know exactly at what point we are uncomfortable in the sun. But, in order to be completely sure, wear sunscreen as much as you can. This is particularly true if you are fair-skinned and/or more prone to sunburn.