Method for Identifying Within a Mammal a DNA encoding a Physiologically Active Polypeptide

摘要

The present inventors found that a physiological effect of a particular DNA can be detected independently within mice into which a pool of various DNAs in various quantities has been introduced. This finding suggests that it is possible to identify a DNA having a particular physiological effect by successively fractionating a pool of various DNAs in various quantities using the particular physiological effect seen within a mammal as an index. Such a method of screening will have the advantage of saving much time and effort as required in conventional screenings such as those utilizing transgenic and knockout mice. Furthermore, the method of screening has the additional advantage of enabling the identification of a DNA having a physiological activity, for example, even when the cells producing a physiologically active substance cannot be maintained in vitro or in immunodeficient animals, or when the cells change their characteristics during passage and stop producing the physiologically active substance.