So what is life, you ask? You require a need to define life? Personally, I view life from a biological point of view. All organisms have life, therefore they need to be able to respire, grow and reproduce. Anything that cannot is no longer living (dead) or not an organism in the first place.

You must remember that in molecular biology, whilst performing the steps in cloning we are always using cells (bacterial and yeast cells as you have mentioned) to transfer cells from one host cell to another. I’m sure many cells have undergone cell death during these stages and yet, since they are bacterial cells there has not been any objection to using such cells in this way. Therefore the taking of life or murder so to speak, of specific organism is subjective. Bacterial cells after all, do respire, grow, and reproduce, thus, they are life.

So, we come to answer the question whether substituting a cell’s entire genome with another is murder or killing the cells. It is not killing or murder, in my opinion. To kill something or murder something is to deliberately stop a once living organism from respiring, and therefore any chance of growing and reproducing. It is not killing or murder; in fact, it is simply “altering” the state of the organism. It is genetic engineering on a larger scale. For example, your analogy with the brain transplant in a human. It’s basically not murder, but an alteration of that person. But of course this is unethical, tho dependent upon the circumstances. And so, why would it be any different to that of altering a cell’s genome? It’s not. It is immoral, yet it is NOT murder. I think simply it is because bacterial cells are invisible to the naked eye and are often associated by humans to be negative (germs, food poisoning, etc), that their life becomes less important to us. And it is even less considered immoral to work with bacterial cells because cloning often encourages them to grow and reproduce, therefore encouraging life, since the whole purpose of using bacterial cells in cloning is to transfer genes, or in this case to breed and promote certain genes to the next generation of cells.

Then we have the dilemma about creating ‘synthetic cells’. Personally, I encourage this advancement and look forward to the day that is it possible in science to do so. However, although we are creating synthetic cells, they are basically living cells. You may then argue that they are more robotic-like in nature synthesised by us humans for a purpose and are not at all considered to be human or living things. It does indeed bring about ethical issues, especially if these cells are human type. It reminds me of a movie I had watched, one of my favourites. You should watch it one day. The movie is “A.I.”. It’s about a robot boy who longs for the love from his human mother. After there is no longer a purpose for him, he was abandoned. It raises many ethical issues and makes you question what is real or human. A very interesting movie you should watch one day.