In this paper we present ARMEDA II, a project designed to integrate distributed heterogeneous medical and genetic databases in support of genomic medicine. In this project, we have followed a "virtual repository" or VR approach. Although VRs are entities that do not contain any data, but metadata, they give users the perception of being working with local repositories that integrate data from different and remote sources. Our approach is based on two basic operators employed to connect new databases to the system: mapping and unification. The mapping process produces what is called the "virtual conceptual schema" of the newly created VR while the unification process provides tools to create an integrated virtual schema for at least two pre-existing VRs. We tested the current implementation of ARMEDA II using two tumor databases, one containing information from a hospital and the other containing genetic data associated to the tumor samples. The performance of the system was also evaluated using a pre-created set of 30 queries. For all queries the test yielded promising results since the system successfully retrieved the correct information. The ARMEDA II project is the current version of an ongoing project developed in the framework of an European Commission funded project.