[Gene testings in relation with gene diagnosis and therapy]

Recent advances in the molecular biology research have devoted greatly to the clinical applications of genetic informations. Gene diagnosis and therapy is a new medical field to deal with these applications. Nowadays diseases related with gene abnormalities have been shown to reach 8,450, and gene testings to cover all these should be very wide and variable. So that any one of the clinical laboratories in a hospital or even research institutes and laboratory centers should not be able to handle all the testings. A model system to promote gene testings effectively in Japan, which includes a special department in a hospital and limited specifications to the individual laboratories or centers, were presented. In the case of monogenic genetic disorders, gene testing results are useful not only to confirm clinical diagnosis but to predict future development of disorders preclinically and even during the prenatal or pregestational period. Accordingly, these may evoke critical ethical and social problems. Many of common diseases are polygenic in nature and gene testings in these disorders are not directed to the diagnosis but are quite useful to see the individual characteristics of the patients related to the special phenotypes or even the fate of disease process. Acquired malignancies are known to be resulted from a somatic gene mutation and progress by the associations of further abnormalities. Only limited gene testings are already now in use. Wide future development in this field is expected after getting detailed meanings of gene testings in the individual cancers. Gene testings for infectious diseases are known to be quite effective on the early and accurate diagnosis, and many of these are already covered by the health insurance. In conclusion, gene testings are quite important but variable and laboratory personnel should not be able to deal all of these properly. Considering future development of gene therapy, rapid establishment in a hospital of a special department, Department of Gene Diagnosis and Therapy, which is consisted from 3 divisions such as genetic counseling, gene testing and management, and monitoring and adviser of gene therapy, is highly recommended.