Just thinking about viruses makes me angry and a bit afraid. Viruses are just bad DNA wrapped in a coat. These things are not even alive but reproduce more efficiently than anything else because they are parasites. Its very hard to target them with general purpose drugs because there's so little to target. Half of our DNA is just old viruses which every cell in our body reproduces for no reason. They won but they're not even alive or trying to win. There's just something terrifying about seeing something so mechanical and lifeless yet so powerful against life. I hate them so much.
I think these are called retroviruses [1]. Not an expert but if I remember correctly, that DNA can sometimes mutate and turn into something useful and this has happened before so they're not totally useless. But most of the time that DNA is inactivated, non-coding so it doesn't make any proteins.
The fun part is when you realize that the DNA in the nucleus of the cell is only the majority of our genetic information. There is DNA im the mitochondria and there are many side channels which carry genetics. We have a far journey ahead to even understand what we can already map. Not to disparage the efforts done but there is much more to this
If it's some consolation, I've just listened to a recent podcast on This Week in Virology (as recommended by another comment on this post. And they are talking about research that uses the CMV virus which has certain properties that make it a very effective and crucially long lasting vector that can potentially protect us against all manner of infections and cancers.
Placenta proteins are apparently a left over from ancient viruses. They aren't killing machines, they are a data sharing feature in a very complex system. I love viruses.
Viruses have some characteristics of life (they replicate and evolve), but they don't have any metabolic processes and can't exist independently, so they're usually not considered "alive" in the same way cells are.
They don't grow, they don't have a life cycle, they don't consume or expend energy, or do anything on their own, really. They're merely (quite mechanical) clumps of self replicating generic material.
