CDKN2A and xeroderma pigmentosum: The most common inherited genetic defects associated with a predisposition to developing melanoma are the cell cycle regulating genes: CDKN2A, CDK4, a gene responsible for skin pigmentation: MC1R, and the genetic disorder xeroderma pigmentosum (XP) that disrupts the proper repair of UV induced DNA damage thereby leading to a higher mutation rate (10–17).