The localisation and identification of the genes for human diseases are most important aspects of human gene mapping. The identification of a disease gene immediately defines the function of the respective chromosomal region. In other words, the identification and characterisation of morbid mutations provide a short-cut to the definition of specific functions of certain parts of the human genome. Professor Leena Peltonen Palotie has been awarded the Anders Jahre prize for young scientists for her basic research into hereditary diseases, particularly the Marfan syndrome and aspartyl-glucosaminuria.