Identification of the Genetic Mutation Responsible for Segmental Dysplastic Nevi

Dysplastic (atypical) melanocytic (DMN) nevi have been identified as being potential precursors of melanoma and markers for patients at risk of developing primary melanoma1. In addition, having an increased number of nevi is associated with increased risk1. DMN are present in 2-5% of white adults in the U.S. population and international studies have documented up to 18% prevalence2. These lesions may be present in at least 17% of white adults with melanoma and 20-50% of melanomas may arise in nevi and atypical nevi2. The exact gene(s) involved in the development of nevi have yet to be elucidated.

Segmental dysplastic nevi are nevi that are restricted to one area of the body3. This condition is much rarer than the occurrence of dysplastic nevi, but nonetheless, may involve the same genetic mutation. The pattern of distribution in SDN is thought to result from mosaicism, i.e. the part of the body that expresses the dysplastic nevi has a mutation in a gene, however, the rest of the body does not contain this same mutation. Other mosaic disorders that have been studied in greater detail than SDN have been shown to be caused by a single gene mutation4. It appears that SDN is no different and that it too is caused by a mutation in a single gene, however, this gene is not yet known.

In this study we will perform a genetic analysis of tissue from a patient known to have SDN. With the information we gather from this analysis, we may be able to find the gene responsible for the development of dysplastic nevi.

Primary Research Objective:

To investigate the genetic mutation involved in the development of dysplastic nevi by examining a patient with SDN.