To provide an information processor which selects information with high priority out of a great number of pieces of information including information regarding genes according to their connections.

Of a data processing system, this device includes means for managing data objects and giving priority according to their connections, i.e., i) one or more 'storage means' which store the data objects, ii) a 'retrieving means' which regards one or more arbitrary data objects as retrieval keys and reads out of the 'storage means' data objects including the retrieval keys and/or data objects included in the data objects including the retrieval keys, and iii) a 'connection retrieving means' which regards two or more arbitrary data objects as end-point keys, reads out of the 'storage means' one or more data objects connecting the end-point keys, and outputs them as ones having high priority.