Historically, Contract Research Organizations (CROs) have played a significant role in the design, execution, monitoring, and data analysis of clinical trials. Most small pharmaceutical and biotechnology companies rely on the services CROs provide in order to conduct national or international clinical trials mostly because without their contribution the companies would not be able to conduct such studies. Nevertheless, it’s becoming more and more common for large companies to subcontract their researches to CROs in order to lower operational costs and expedite their investigations by hiring experts in design, execution, and oversight of clinical trials. This partnership between pharmaceutical/biotechnology companies and CROs has been the conventional or standard system in industry-sponsored clinical trials and, so far, it has delivered excellent results. However, some critics argue that the current interaction among sponsors, CROs, and academic experts—which also play an important b
leukaemialymphomaresearch.org.uk A DNA library is a collection of cloned DNA fragments stored in host cells (usually bacteria), which constitute an organism’s entire genome. There are also cDNA (complementary DNA) libraries that are made through the reverse transcription of messenger RNA isolated from an organism. Such cDNA libraries give insight of which genes are actively transcribed in an organism; one drawback is that in cDNA libraries not all genes are represented. DNA libraries are created by cutting the DN A using mechanical methods or with a restriction endonuclease, and then cloning the fragments into vectors to produce recombinant DNA. Vectors are ‘delivery vehicles’ that can carry inserted DNA into host cells; there are several types, which differ in their insert capacity (the amount of DNA that can be inserted). Some of these vectors are: plasmids, bacterial artificial chromosome (BAC), cosmids, yeast artificial chromosome (YAC), and bacteriophage λ [1]. Plasmids