fossilesquegreat grandaddy bur oak
Remember_the_toothDendrologists: [heavy breathing]
In all seriousness, isn’t it pretty unlikely that alien life could interbreed with terran life even if they also used DNA with the same bases?
It’s extremely unlikely that their DNA has the same translation semantics into proteins.
Not unless there is a common ancestor, which is theoretically possible. But yeah, extremely unlikely.
Wow. So I went looking if people actually knew when our codon system appeared.
Turns out that there are 26 slightly different systems on Earth right now, and there are good reasons to expect random alien life to have a system that looks like ours, but is different enough to not be compatible.