INTRODUCTION In order to conduct studies of mental retardation of a genetic origin over the GIRMOGEN network, a computerised register of cases needs to be set up. MATERIALS AND METHODS This register requires the implementation of a computer application consisting of a series of management programs together with the actual database. The aims of this work are: a) To analyse all the infrastructural, scientific and technical conditioning factors that allow the computer application and the databases associated to the register to be designed; b) To design all the elements that go to make up the application, namely, the application engine, consisting of all the programs responsible for providing all the operative capabilities, and the database for storing all the data structures with the variables related to the research; c) Implementing all the designs that are developed; and d) Drawing up the security protocols and work procedures involved in running the application. RESULTS The result of all this process is the Girmogen-Pro software application, which includes all the capabilities needed to enable it to fulfil the scientific goals of the study. It includes the security measures required to comply with the current laws regarding the handling of files containing personal information. Furthermore, the data structures that will constitute the registers to be used in the study were also been built. CONCLUSIONS This process does not end with the implementation of the designs, since an ongoing assessment process is also performed with the aim of optimising the data structures that contain the variables that go to make up the register, so as to ensure it fits the scientific objectives of the study as well as possible.