Scientists Strive for Better Understanding of Skin Cancer Risk
Using a model developed by dairy cow breeders, researchers are refining the way they predict human disease risk.
--by Suzanne Boothby
Sun exposure is one of the main ways to increase your chances of developing skin cancer, but scientists still don’t know why some sun worshipers develop cancer while others do not.
New research published in the journal Genetics from scientists at the University of Alabama at Birmingham (UAB) and the University of Wisconsin–Madison concludes that the risk of skin cancer involves many genetic factors, including family history, ethnicity, and genetic variations in individuals.
The researchers developed a more precise model for assessing risk—one that was first developed to breed better dairy cows. The technique, called whole-genome marker-enabled prediction (WGP), uses all the available genetic information jointly, instead of looking at a few variants associated with genes known to cause a given disease. The scientists theorized that WGP may be better at predicting the risk of complex diseases, as it has been used successfully in plant and animal breeding programs.
The Expert Take
Better prediction of genetic risk for skin cancer could lead to stronger prevention efforts by providing personalized information to patients and hopefully, helping detect the disease early.
“Although there is no doubt that sun exposure increases your risk for skin cancer, it isn't clear how much of a risk it poses to each individual,” said Mark Johnston, Editor-in-Chief of Genetics. “This new model for assessing risk should prove useful to health care providers and public health officials, who play a crucial role in educating people about preventing skin cancer."
The researchers admit they are still refining the technique, but are pleased with results so far.
“While many aspects of this technique are still under development, our new predictive model was able to account for a large proportion of each person’s predisposition for skin cancer,” said lead study author Ana Inés Vázquez, Ph.D., from UAB's Department of Biostatistics. “We hope this study will ultimately contribute to a better understanding of the genetics of complex traits and diseases—such an understanding is essential for the development of methods that can be used for early and improved prediction of genetic predisposition to diseases.”
This research is also noteworthy because scientists took an animal model and applied it to humans in a unique and inventive way.
“Dr. Vázquez’s work represents one of the first uses of WGP to predict risk for a complex disease phenotype with clinical relevance,” said study author David Allison, Ph.D., Associate Dean for science at the UAB School of Public Health. “Her story is one of interdisciplinary creativity in applying concepts developed in animal breeding to human population genetics, which reflects our core approach to research at UAB.”
Skin cancer is the most common form of cancer, and it incidence continues to rise. While ultraviolet (UV) exposure and light skin pigmentation are major risk factors for all types of skin cancer, evidence suggests that genetic factors also play a role, independent of skin pigmentation, according to the new study.
While many aspects of the risk model are still under development, the results could lead to a clearer understanding of why some people develop cancer.
“More developments are needed before this methodology can be considered for establishing prevention strategies,” Vázquez said. “We are enthusiastic about the prospects of further developing this methodology for the prediction of human traits and diseases.”
Source and Method
Scientists used phenotypic and genetic information from more than 5,000 familial participants in the Framingham Heart Study to develop various models for assessing skin cancer risk.
The risk evaluation model included standard risk factors, such as gender, and then developed more predictive models using information on family history, ethnicity, and data from 41,000 genetic markers across the human genome. The predictive power of each model was evaluated, with the best prediction accuracy obtained from models that included all predictive risk factors.
Previous studies, including this 2008 British study, have shown that genetic factors play an important role in predisposition to skin cancer.