1. A system for ontology driven data mining, comprising: an informatics system coupled to a plurality of data sources, the informatics system comprising a processor and a non-transitory computer readable medium comprising instructions for: receiving an input from one or more of the plurality of data sources, wherein the input is structured data; creating a graph representation of the input by translating the structured data to a graph representation of the structured data, creating a source ontology based on the graph representation of the structured data and creating the graph representation of the input based on the source ontology and the graph representation of the structured data; obtaining a graph representation of a domain ontology, wherein the domain ontology comprises a set of concepts and a set of relationships and the domain ontology comprises a Simple Knowledge Organization System (SKOS) representation of the unified medical language system (UMLS); mapping the graph representation of the input to the graph representation of the domain ontology to create a unified graph comprising the graph representation of the input and the graph of the domain ontology; constructing a query based on at least one of the set of concepts or at least one of the set of relationships of the domain ontology; and searching the unified graph based on the query to obtain data of the input associated with at least one concept or the at least one relationship.