Is Skin Cancer Genetic?
So, is skin cancer genetic? In the vast majority of circumstances, excess sun or UV exposure is the primary cause of the disease’s appearance—but that doesn’t mean that genetics are absent from the equation. Here’s the bottom line: both melanoma and other common forms of skin cancer are likely to run in families.
Here’s what you should know about genes and skin cancer:
- Basal cell skin cancers are more likely in patients with pathogenic variants of the PTCH1 and PTCH2 genes. This is because those with these variants are more likely to develop basal cell nevus syndrome (AKA Gorlin-Goltz syndrome), a complex disease characterized by the increased likelihood of skin cancer, as well as various other ailments and conditions.
- The following genetic syndromes are all associated with an increased risk of squamous cell skin cancers: Epidermolysis bullosa (cracking and blistering of the skin); fanconi anemia (increased incidence of solid and blood-related growths); oculocutaneous albinism (absence of skin pigmentation).
- Xeroderma pigmentosum—dramatically increased sensitivity to sunlight—is associated with higher occurrences of basal cell, squamous cell, and melanoma skin cancers, especially in the first decade of life. The trait is genetic and recessive.
- Is melanoma skin cancer hereditary? This deadly type of skin cancer is also associated with certain genetic risk factors. Particularly, pathogenic variants of the gene CDKN2A have been associated with up to 35% or even 40% of familial melanoma skin cancers. Pathogenic variants of other genes, including CDK4, MITF, and BAP1, are all also associated with an increased risk of skin cancer.
It bears repeating that genetics are certainly not always to blame for skin cancer occurrence. For example, researchers from Stanford have estimated that only 5% to 10% of melanoma skin cancers are hereditary.
Skin Cancer Risk: Other Hereditary Factors
Certain physical characteristics, including lighter skin, blue or green eyes, and lighter-colored hair, are all—quite obviously—transmissible from parent to child. However, it’s important to point out that these factors already put individuals at a higher-than-average risk of skin cancer. Those who have these traits should take extra care to protect themselves from excess sun exposure.
Skin Cancer Risk: Confounding, Non-Genetic Factors
As we noted from the outset, the increased likelihood of skin cancer in a given family is not necessarily the result of genetics; it may also be a byproduct of shared behaviors! Members of the same family might be exposed to similar levels of UV light, for example, if they spend similar amounts of time outside, live in an area with higher elevation (and higher levels of UV exposure), or are not in the habit of applying sunscreen. Similar reasons explain why skin cancer might turn up multiple times in a family or close circle of friends, even though it is not at all contagious.
Controlling your own behavior, and encouraging good behavior among others, could help to decrease the risk of skin cancer across your whole family.
For Treatment, Consider Image-Guided SRT
Image-Guided SRT is a surgery-free treatment for skin cancer that is just as effective as Mohs surgery. If you or a loved one is diagnosed with basal cell, squamous cell, or another common form of skin cancer, Image-Guided SRT can treat the disease with no risk of scarring and fewer interruptions to your lifestyle. Find out how it works today, and ask your doctor if it’s the right choice for you.