MPS has found its way to the analysis of single eukaryotic cells or even cell-free DNA in blood samples,e.g. of transplantation. Of considerable importance is the socio-ethical aspect of data ownership, privacy, informed consent, and result report to the study participant. While the technology is advancing rapidly, legislation is lagging behind due to the globalisation of data requisition, banking and sharing. Keywords:Sequencing, Diagnosis, Ethics, Consent, Data management Core tip:Despite the great excitement about the opportunities that massively parallel sequencing (MPS) bears for the promotion of,e.g., transplant science, personalized medicine faces the challenge to guarantee privacy of data and findings. Here, some applications of MPS in transplant science are mentioned, and concerns and challenges in data analysis and management are discussed. == MASSIVELY PARALLEL SEQUENCING == Massively parallel sequencing (MPS) is an alias of the probably more popular term next-generation sequencing (NGS). In this article the term next-generation sequencing will be avoided for the simple reason that next is a relative term in matter of time. If Sangers and Maxam and Gilberts ground RWJ-67657 breaking inventions of DNA sequencing in 1974 are counted as the first generation, then the automation of Sangers method could be considered the next or second generation. Further, the next step which in 2005 lead to the development of machines which were able to sequence millions of fragments of DNA RWJ-67657 simultaneously would certainly have to be called the next-next-generation or third generation[1]. And the next generation of technological improvement is on its way: the 4thgeneration of sequencing methodology will utilize entire strands of DNA without the need of fragmentation, and will become cheaper, and more precise, and simpler to handle bioinformatically. In order to avoid counting generations of technological advancement, the term MPS, or MPS for short, seems more applicable and will be used herein. A variety of technical approaches to MPS exist, all of them have been reviewed in detail (for an excellent overview please see,e.g.[2]. Briefly, the general principle relies on (1) the fragmentation of DNA/RNA, optionally followed by fragment size selection; (2) amplification of the fragments; and (3) sequencing of the fragments. Currently, the length of those sequences can be up to 800 bp, depending on the vendor. As the RWJ-67657 fragmentation step generates random breakpoints in the DNA backbone, so will the sequenced fragments in Step 3 3 be at a random position of the DNA or RNA. This is where the individual small pieces of sequence information will have to be bioinformatically stitched together, assembled, being a challenge to which there are plenty of approaches with slightly different quality, depending on the analysis pipeline of choice. The applications of MPS are RWJ-67657 overwhelming and offer never seen before opportunities to study genomes, exomes, transcriptomes, and chromosomal rearrangements and secondary modifications like methylation of Tgfb3 DNA and alkylation RWJ-67657 of RNA. Through its unbiased template-free approach, it is now also possible to sequence DNA and RNA of novel species inde novoassembly analyses and thus accelerate discovery of,e.g., ontological relationships[3], and even discover novel RNA species[4]. Input amounts in the low ng-range for some MPS applications make it possible to study biological samples in a detail which could not have been envisioned before[5]. MPS has found its way to the analysis of single eukaryotic cells or even cell-free DNA in blood samples,e.g. for non-invasive prenatal diagnosis[6]. == PERSONALIZED TREATMENT == Following transplantation, drug treatment must be carefully adjusted to prevent rejection. Drug metabolism is influenced by a large variety of factors such as age, gender, disease, dose, drug-drug interaction, and metabolic competence. Differences in the genotype (polymorphisms) can be linked with.