Sets of genes are identified that show modulated activity in hyperpigmented sun-exposed (HE) and non-hyperpigmented sun-exposed (NHE) skin, when compared to non-hyperpigmented non-exposed (NHNE) skin. The modulated sets of genes reveal important information about the genetic changes that take place in skin as a result of environmental exposure and damage. The modulated sets of genes may be used to fabricate custom DNA microarrays for evaluating patients with skin diseases or disorders. The microarrays may also be used to screen new substances for treating skin diseases and disorders. The modulated gene sets, and substances that target them, may also be used to develop therapies for individuals who suffer from hypopigmentation, such as those with Fitzpatrick type I skin or vitiligo.
