It's an overstatement to say that viruses are "unrelated to the rest of life". They have RNA or even DNA, which almost certainly makes them related. If we foun

It's an overstatement to say that viruses are "unrelated to the rest of life". They have RNA or even DNA, which almost certainly makes them related. If we found a living organism which didn't have RNA or DNA, that would be a good candidate for an alien. It would help if we found it on another planet though.