Can a Mutation Happen in a Gene?

Bacteria can come to another bacteria, and actually while they're living, share DNA. And so you can have a bacteria that has a particular gene, that one bacteria doesn't. And give it that gene, and that gene may translate into a protein that now has an enzyme. This is because the only way that human beings can share DNA is when male-female creat offspring. That's the only way they share DNA is by creating another offspring. So it's not- It can just happen in any single gene, but because what we have is one, there's heaps of bacteria,. Two, the doubling time is so quick, that it's not unlikely for a mutation to be