Background: Little is known about the impact of knowledge of CDKN2A and MC1R genotype on melanoma prevention behaviors like sun avoidance and skin examination in the context of familial melanoma.
Methods: Seventy-three adults with a family history of melanoma were randomly assigned to be offered individualized CDKN2A and MC1R genotyping results in the context of a genetic counseling session, or the standard practice of not being offered counseling or disclosure of genotyping results. Mixed effects or longitudinal logistic models were used to determine whether the intervention affected change in sun protection habits, skin examinations, and perception and beliefs related to melanoma risk, prevention, and genetic counseling.
Results: All participants in the intervention group who attended genetic counseling sessions chose to receive their test results. From baseline to follow-up, participants in the intervention group reported an increase in the frequency of skin self-examinations compared with a slight decrease in the control group (P = 0.002). Participants in the intervention group reported a smaller decrease in frequency of wearing a shirt with long sleeves than did participants in the control group (P = 0.047). No effect of the intervention was noted for other outcomes.
Conclusions: Feedback of CDKN2A and MC1R genotype among families without known pathogenic CDKN2A mutations does not seem to decrease sun protection behaviors.
Impact: While disclosure of CDKN2A and MC1R genotype did not have negative effects on prevention, the benefits of communicating this information remain unclear. The small number of families who tested positive for CDKN2A mutations in this study is a limitation.