Describe the genetic mutations found in atypical melanocytic nevi.

Mutations in susceptibility genes have been detected in atypical nevi including cyclin-dependent kinase inhibitor 2A (CDKN2A) and cyclin-dependent kinase 4 (CDK4). Furthermore, a high incidence of B-Raf mutations has also been detected in atypical nevi. It is thought that these mutations may be due to ultraviolet radiation because patients with atypical nevi may have a decreased ability to repair ultraviolet light–induced DNA damage.

Weatherhead SC, Haniffa M, Lawrence CM: Melanomas arising from naevi and de novo melanomas: does origin matter? Br J Dermatol 156:72–76, 2007.