In moles, these cells grow briefly before stopping, forming a benign spot. In melanoma, however, the cells continue to divide uncontrollably. A high mole count is a major risk factor for melanoma, with about one-third of melanomas developing from existing moles.
Associate Professor Matthew Law, who leads the Genetics and Skin Cancer Lab at QIMR Berghofer, said that while public health campaigns and treatments have improved outcomes, melanoma remains a major health challenge in Australia.
“Australia still has the highest incidence of melanoma in the world, and around 1,400 people die from the disease each year,” he said.
“Immunotherapies have improved survival, but they do not work for about half of patients with advanced melanoma, so new treatment approaches are needed.”
One gene identified in the study, SIKE1, plays a role in regulating immune responses to viral infections.
Researchers believe that if this gene malfunctions, it may impair the immune system’s ability to detect and destroy abnormal melanocytes, potentially allowing melanoma to develop. This makes it a possible target for future therapies.
The study also enabled the development of a polygenic risk score to predict individuals more likely to have a high mole count.
This tool could be incorporated into melanoma screening programs to improve early detection for those at higher genetic risk.
Lead author, Shanika Jayasinghe, said the findings build on decades of skin cancer research and help explain why some individuals are more susceptible to developing moles and melanoma.
Researchers say their next steps will include analysing larger datasets to identify additional genetic factors and investigating whether existing drugs could target the newly identified pathways.