In 2007, the Nobel Prize in Physiology and Medicine was awarded to Martin Evans, Mario Cappecchiemu and Olivier Smithiesowi. Martin Evans has been honored for the isolation of pluripotent mouse embryonic stem cells (ES cells), two other researchers for developing methods of genetic modification of these komórek.Tutaj presents the history of obtaining embryonic stem cells, methods of inducing their differentiation targeted in vivo and in vitro, as well as selected issues associated with the potential use of these cells for therapy.

This article is focused on problems related to application of mice knock-outs used in neurobiology. Diverse genetical background, genotype of mouse strain 129 (the main source of embryonic stem cells), developmental defects, pleiotropy and compensation make the interpretation of results from knock-out models difficult. The use of time- and space-specific "knock-outs of second generation", introduction of transgenes that reverse the effect of gene knock-outs, blocking of genes by antisense mRNA or point mutations may aid in eliminating some of these problems.