ABSTRACT
The application of nucleic acid diagnostic methods to pathology will improve our understanding of the molecular mechanisms causing human disease and provide a means of screening for individuals at risk. Although these methods can be applied to extracted nucleic acids for an accurate diagnosis it is often necessary to identify the cells carrying the target nucleic acids using in situ techniques. These mutations include point mutations, truncations, amplifications, and translocations characteristic of oncogene activation and point mutations, deletions, loss of heterozygosity, microsatellite instability and promoter hypermethylation, which are characteristic of tumor-suppressor genes. In addition to advancing the understanding of pathological mechanisms underlying the transformation process, the cloning and sequencing of the genes altered by the translocations have allowed PCR primers to be developed to detect the translocation for diagnosis and monitoring of patients. This hypermethylation correlates with transcriptional inhibition that can serve as an alternative to promoter or coding region mutations for the inactivation of tumor-suppressor genes.
