Recent press reports have highlighted what appears to be a major advance towards the creation of artificial life, when they reported the total synthesis of the first chromosome of an organism, a yeast, that is biologically more similar to humans than to bacteria. The study was conducted by researchers at the Johns Hopkins and New York universities in the United States, in what was an interesting innovation in the approach to this type of research. The new chromosome has substantial differences with respect to the original model. These modifications, which result in it being roughly 14% shorter, were introduced in order to make it more stable and flexible from a genetic point of view. According to the authors, this flexibility will enable it to be modified in vivo to change a specific property aimed at, for example, the production of antibiotics or biofuels. Although the synthetic chromosome has several differences with respect to the original, the yeasts that contain it are biologically indistinguishable from natural yeasts.
This is one further step in the field of Synthetic Biology, which already had huge media coverage in 2010, with the synthesis of the first whole genome. At that time it was Craig Venter’s group who made a copy of a bacterial chromosome that was shown to be perfectly functional, as in the case of the yeast. Interestingly, the size of the bacterial molecule was four times larger than the one synthesised now and essentially identical to the original, unlike the yeast chromosome, which is significantly different. After this breakthrough, which already foreshadowed the current one, a couple of years later (in 2012) Professor Eduardo Moreno produced a new species of fly, synthetic Drosophila, using an essentially different approach based on genetic modification.
The synthesis of the yeast chromosome was without question a major step for Synthetic Biology, an area of research with a novel focus on biotechnological research, using advances in biological techniques and knowledge towards bioengineering, the synthetic genome, synthesis of protocells and finally, towards artificial molecular biology. The tools used in Synthetic Biology are basically Molecular Biology techniques developed in the later decades of the last century that have enabled advances to be made in fields like gene therapy and the production of genetically modified organisms.
This latter discovery shows that it is only a question of time and effort, since the technology has already been available for some time. This will probably be the start of a race in two directions: on one hand, the synthesis of genomes of increasingly complex organisms (including humans) and, on the other, the production of completely synthetic cells, in what would be the closest thing to artificial life.
Following on from this news, statements from expert researchers in this field have been published, such as that of Harvard University professor George Church, indicating the possibility of generating a “healthy” whole human genome. According to this investigator, the only limitation for Synthetic Biology is imagination. This field has been advancing extraordinarily quickly, since on one hand technical tools are already available and, on the other, the concept is relatively simple: use the “parts” that nature gives us to construct a new “whole”.
However, this new technology raises major bioethical issues, such as risks for the environment, biosafety, distribution of resources, long-term impact of the sudden alteration of the evolutionary process or the manipulation of human genetic patrimony with the ever closer possibility of producing human beings on demand from zero. Hence, the establishment of an ethical framework based on respect for the human person is urgent
Dr. D. José Miguel Hernández Andreu
Professor of Biochemistry and Molecular Biology Catholic University of Valencia
Member of the Bioethics Observatory
 N. Annaluru et al., “Total synthesis of a functional designer eukaryotic chromosome,” Science, doi:10.1126/science.1249252, (2014)
 D.G. Gibson et al. “Creation of a bacterial cell controlled by a chemically synthesized genome,” Science, published online May 20, 2010.
 E. Moreno. Design and Construction of “Synthetic Species”. PLoS ONE 7(7): e39054. (2012)