it's still too experimental. a lot of this stuff is just people rushing to be first and get some fame/notoriety. that's why you'll see chinks and jews playing with it recklessly.  because the op is talking about dealing with cells (and not on a human), and in fact something like growing your own genetically engineered humans likely also will start with the same starting point (of a zygote), it should be straightforward to do things like screen out specific cells that haven't got the changes, or do sequencing on one of the cells. with sequencing getting cheaper it would be feasible to do something like: apply a specific change, sequence some to see it was applied successfully, culture the cells, then apply another change and so on. the risk in something like that is low, assuming there is a good understanding of what the changes will cause (i.e. we know what the changes will do, since we're still deciphering the genetic code that's the most dangerous part of this kind of work). it's when you start to inject it into humans that you open a can of worms. because if you change enough of your cells your body is going to react to that, the immune system might even attack them because it sees them as abnormal/foreign. so i wouldn't be using this shit on myself (not until we have a much better understanding of things than we do now). it is much safer to play around with genetically engineering your own progeny from cells than your own body. and "safe" assumes you know what the changes will do. the chink who changed the two babies to try to make them smarter and immune to hiv didn't actually know what the consequences would be, he just did it. the tl;dr for people's concerns is genes work together, so changing even a few that you don't know everything they're involved with could have unintended consequences.
Ireland