Lars Maria Theo Eijssen was born on May 30th 1976 in the southern Dutch village Schimmert. From 1988 until 1994 he attended secondary school, Gymnasium, at the Stella Maris College in Meerssen. From a broad interest of scientific programs he chose to be a medical student. In order to do so, he first did an intensive course in chemistry at the James Boswell Institute of Utrecht University. After this, he started enthusiastically with medical training at Maastricht University. Because he was also still interested in more technical fields, Lars started in 1995 with the program of Knowledge Engineering at both Maastricht University and the Belgian Hasselt University. As part of this program, he followed a course in computer science at Baylor University, Waco, Texas, USA for a month and participated in a number of projects related to logistics and information technology for several companies.

After completion of a scientific internship at the Department of Epidemiology of Maastricht University, Lars received the Masters of Medicine cum laude in the year 1999. After finishing an internship at the Department of Genetics and Cell Biology of the same university, he also obtained the Masters of Science in Knowledge Engineering, specialization business and applied mathematics, cum laude. Based on this, he was also granted an official certificate of equality to the Belgian Licentiate Applied Computer Science by the Flemish Department of Education.

In the year 2000, Lars started as a PhD student at the brand new Department of Population Genetics, Genomics & Bioinformatics at Maastricht University. Apart from his own project, he also assisted in setting up several other activities, amongst which many ICT related tasks within the group. In 2006, the completion of the PhD project lead to publication and defense of the PhD thesis 'Analysis of microarray gene expression data sets' with Prof.dr. J.P.M. Geraedts as promotor.

Lars also helped in assisting non-profit organizations with respect to information technology, development of graphical design, websites and printing. Having again more freedom of choice with respect to time planning with the finishing of his PhD, he strongly focuses on applying his ICT knowledge as a professional.