Nature possesses scant possibilities to bring forth completely new life forms from one generation to the next. Crossing two different species quickly leads to a genetic cul-de-sac. A horse and a donkey can indeed produce a mule, but this hybrid is unable to reproduce itself. Nevertheless, this “natural” emergency brake mechanism isn’t universally operative. Quite a few crossed plant species are very much in a position to yield seeds that reproduce superior traits. But what about when human beings use synthetic biology to go out into uncharted territory, to exploit technology to evade natural reproduction, and to create synthetic hybrids that have never before existed in this world?
Here, the concept of biobricks comes into play. With this approach, synthetic biologists create individual biological building blocks with particular functions just as they occur in nature in order to intentionally assemble them into a new life form. If somebody thinks it would be a good idea for plants to glow, then they can be equipped with the glowing function of another form of life. After all, why rewrite nature’s software from scratch when these features and components, tried and tested over millions of years, are already available? But can a synthetic hybrid actually survive in the rough and tumble world of nature? And are we justifiably afraid of a Frankenstein’s monster getting out of control?