[The present status and future prospect of the molecular diagnostic tests]

Assays for DNA or RNA sequences to diagnose infectious, neoplastic and genetic diseases have been widely used through recent progress in the molecular biology and biotechnology, and are now essential in care of patients under the advanced medicine through earlier and more accurate diagnosis. Automated systems have been developed for amplification and detection of nucleic acid sequence for infectious agents, using various nucleic acid amplification technology such as PCR. A fully automated PCR system and automated extraction of specific sequence for infectious agents such as hepatitis C virus RNA has been developed. These automated systems have provided improvement of not only assay efficiency but also quality control of the tests and have contributed to the standardization of them. Importance of development of systems for quality assessment and laboratory accreditation has been emphasized, particularly in those that still have been performed with manual methods. Based on the information on the genome sequence as the outcome of the human genome project, functions of genes and proteins have been studied by post-genomics such as expression profiling using DNA microarray, proteomics, single nucleotide polymorphisms analysis, coupled with bioinformatics. Along with advances in pharmacogenomics, these studies have raised the prospect of the development of tests for individualized medicine based on genetic information such as those predicting individual susceptibility to diseases for prevention and responsiveness to drugs for choice of treatment. For practice of such medicine, each genetic information and tests for it must be carefully evaluated and determined whether it is appropriate for cost-effective medicine through contributions to efficient process of decision-makings on patient care for prevention or avoidance of diseases and thus to cost savings.