With the introduction of recombinant DNA technology two decades ago, a new class of pharmaceuticals (known as biologics) began to reach patients and proliferate to treat other human diseases. Although the first human recombinant proteins (such as insulin) were analogs for the molecules previously obtained from cadavers or animals, the technology brought about many new therapeutics that were unavailable. This new class of protein therapeutics transformed the panorama of medicine and clinical treatments. Most traditional drugs are small molecules with well-defined chemical structures, such as penicillin and aspirin. In contrast, biologics have rather complex structures that are not easily characterized. In addition to recombinant therapeutic proteins, these biologics include vaccines, polysaccharides, DNA, and cells, among others. Biologics differ mostly from conventional drugs in that their efficacy is not entirely defined by their chemical composition and structure. Slight variations in process conditions may lead to the same protein molecular primary structure, but with a variant folding, imparting different characteristics on the resulting drug. In the past two decades, the Chinese Hamster Ovary Cell (CHO) has become the dominant host system for human recombinant therapeutic proteins. This dominance derives from its ability to perform glycosylation, (which is the process of covalently linking complex carbohydrates to specified sites within the protein1) and other complex post-translational modifications, as well as from the plasticity that enables CHO cells to be transformed from minimal protein secretors to higher-level secretion cells. Seventy percent of all recombinant protein therapeutics is produced on CHO cells2. As patents for many therapeutic proteins expire, non-brand name products will become known. The new products will be challenged to match productivity and quality of the brand products and process engineers will have to achieve product quality, process robustness and consistency. Since the introduction of mammalian cell recombinant proteins as therapeutics, biotechnologists and chemical engineers have manipulated the art to transform cells into very productive factories for these medicines. The introduction of genomic tools in the past years, to bioprocess research has enabled to a better understanding of mammalian cell culture. They have provided insight into the complexity of higher productivities and product quality. With DNA sequencing technologies making giant steps forward, genomic technology will become even more available to the bioprocess community. The sequencing of the CHO genome will lead to a developing time on the biotech industry’s most important host, CHO cells; developing or creating a way towards smarter processes, designer cell lines, and superior quality. References: 1. D.L. Nelson and, M.M. Cox, “Principles of Biochemistry,” Fourth Edition, Freeman and Company (2005). 2. K.P., Jayapal,“Recombinant protein Therapeutics from CHO cells 20 years and Counting,” Chem. Eng. Progress, 103 (10), pp. 40-47 (2007).