**6. Conclusion**

Today, there are various methodological approaches allowing the quantitative and qualitative characterization of cell-free nucleic acids in circulation of hemodialyzed patients. The study od cfDNA in plasma during the hemodialysis began 30 years ago and brought interesting results concerning the apoptotic origin of at least an important fraction of this DNA and increase of its plasma concentration during the hemodialysis session regardless of the used membranes and duration of session. In the past decade, the clearance of cfDNA from plasma was studied not only in hemodialyzed patients, and it was concluded, that it is very rapid (the half-life is given in minutes) and kidney does not play the major role in this process. In last years, the attention is paid to the examination of cell-free ribonucleic acids in the circulation with regard to their use as biomarkers under different pathological conditions. The application of such methodologies in the field of hemodialysis is still awaiting for the researchers, as well as the application of high throughput technologies likes Next Generation Sequencing and array technologies of different design. The connection of new technologies with clinical studies will result not only in clinical benefit but also in deeper insight into basic biological mechanisms of intracellular communication, epigenetic regulation and modulation of immune function at the individualized level leading to truly personalized medicine.
