Creating Life: A Safe and Effective Method
Before we consider ways by which artificial life can be created, it would be useful to be clear as to what we mean by creating life. Let’s confine our attention to biological life, as opposed to computer simulations of living organisms. How we define the creation of life depends on our purpose in attempting to do so. Let’s assume that our goal is to increase our understanding of the nature of life, as well as to develop the ability to control the process, perhaps to the extent that we can create new life forms. Such a goal would rule out considering procreation since, while the latter results in the production of living organisms, it neither requires nor increases our understanding of the process.
The noteworthiness of the achievement of creating life depends on the raw materials used as well as the final product. To use an analogy, consider what we mean by making a cake. We usually think of the process as involving mixing the ingredients — flour, sugar, eggs, water, etc. — to form the dough and then baking the dough in the oven. What about adding water to a cake mix to form the dough, which would likewise be baked in the oven? Would that qualify as making a cake? Clearly, a greater degree of skill is required to make a cake from scratch than to do so using a cake mix. Similarly, it would be a greater achievement to construct a DNA molecule capable of self-replication base pair by base pair than to modify the DNA of an existing organism, such as a virus.
An important consideration in attempting to create new life forms it to ensure that they don’t escape from the laboratory and spread disease by infection or have a harmful effect on the ecology. One way to assure that any organism created cannot survive outside of the laboratory and at the same time guarantee that the life form so created was done from simple molecules and not from any complex organic molecules found in nature is to create life using molecules that are the enantiomers (mirror images) of those present in existing life forms.
For example, to construct a mirror image DNA molecule capable of self-replication, begin by synthesizing the enantiomers of the four nucleotides used as base pairs, and assemble the base pairs in sequence using an existing DNA molecule as a template. To cause the mirror image DNA to replicate, for example, by the polymerase chain reaction (PCR), proceed as you would with conventional PCR replication, replacing all chiral molecules involved with their enantiomers.
Mirror image life could be used to advantage in developing a vaccine against diseases caused by a virus since it avoids the risk of accidental infection. As long as the mirror image organism created requires at least one essential nutrient that consists of chiral molecules, that organism could not survive outside of the laboratory. However, mirror-image versions of organisms such as algae that don’t require any chiral nutrients could create an ecological disaster if they got loose since any organism feeding on them would die of malnutrition. Keeping the mirror image algae in check would require creating a mirror image of an organism that feeds on normal algae.