Nonradioactive arbitrarily primed polymerase chain reaction: a novel technique for detecting genetic defects in skin tumors.

Initiation and progression of melanocytic and non-melanocytic skin tumors are accompanied and probably caused by a variety of genetic defects. In contrast to other human tumors, however, limited amounts of available tissue in skin cancer often hamper extensive genetic studies of native material of early lesions. Therefore, we applied a novel DNA fingerprinting technique based on polymerase chain reaction (PCR), the arbitrarily primed PCR (AP-PCR). This technique enabled us to scan large parts of the genome (about 30 kb/PCR reaction) for somatic mutations starting with minute amounts of tissue. In contrast to previous reports on AP-PCR, we were able to visualize PCR products by a rapid nonradioactive silver-staining technique using a simple device for staining of large polyacrylamide gels. In nine benign and malignant melanocytic skin tumors, the method provided a set of reproducible DNA fingerprints. Genetic defects were detected by comparing the fingerprints of tumor cells and constitutive DNA from blood leukocytes. Since nonradioactive AP-PCR fingerprinting also offers the unique capability to isolate and sequence polymorphic DNA fragments from fingerprint gels, we conclude that this technique seems to be important and practically feasible for elucidating the genetic roots of skin tumors.