The present invention provides a method for deriving an upstream or downstream component of a component necessary for phenotypic alteration of a living organism, the method comprising the steps of: specifying a pathway of interest related to the phenotypic alteration and a reference pathway different from the pathway of interest, and specifying a stimulant of interest and a reference stimulant which respectively stimulate the pathway of interest and the reference pathway; giving the stimulant of interest to the living organism to identify a collection of components of interest necessary for the phenotypic alteration; giving the reference stimulant to the living organism to identify a collection of reference components necessary for the phenotypic alteration; calculating an intersection between the collections of the components of interest and the reference components; and calculating a differential collection by subtracting the intersection from the collection of components of interest.