Re: Is melanoma genetic or are there any other factors?

Hi Dan,

Melanoma is a cancer of cells called melanocytes that are mostly found in the skin. Because of this, the most significant factor leading to melanoma is exposure to UV radiation (sunlight). Surprisingly, sporadic exposure to intense sunlight puts one at higher risk for melanoma than prolonged exposure, possibly because skin infrequently exposed to sunlight has not adapted 1. So, you are less at risk for melanoma if you are out in the sun all the time than if you go out once in a while and get a sunburn each time. People with fairer skin are also more prone to melanoma 1 .

You are right that genetics can play a role in melanoma. One example is a gene that confers a greater risk to developing melanoma is cyclin-dependent kinase inhibitor 2A (CDKN2A). CDKN2A encodes two protein products: p16^Ink4a and p14^ARF, both involved in cell cycle arrest. Cell cycle arrest allows a cell to repair any damaged DNA before it replicates its DNA and divides. So without cell cycle arrest, cells with damaged DNA are able to replicate and pass on the mutations. An accumulation of mutations can lead to cancer. Other genes have been implicated in melanoma progression, but CDKN2A is thought to be involved in 35-40% of melanomas that run in families 1 .

Most of this information is from the National Cancer Institute website: http:// www.cancer.gov/cancertopics/pdq/genetics/skin/HealthProfessional/page4. Much more information can be found on this website, and on the more general NCI website: http://www.cancer.gov/cancertopic s/types/melanoma

I hope this helps!

Sarah