I suspect it very much is a practical skill. I'd be shocked if genetics are the sole determinant in your wit - surely other aspects such as linguistic ability, social skills, knowledge of pop culture, confidence, etc. all contribute to wit. And those can all be trained.
It would take time, of course, and a lot of practice rather than just having it explained to you. But I don't see why it wouldn't be trainable.
It would take time, of course, and a lot of practice rather than just having it explained to you. But I don't see why it wouldn't be trainable.