[quote=@Tlazolteotl]
Are these people with mutations under constant surveillance? Is it possible for someone to get a mutation without anyone noticing?
[/quote]

First off, no, mutations are not under constant surveillance. At least, not legally. There are those with less than noble intentions who do spy on them. That being said, mutations do have their afflictions listed in their medical files. So, if someone wanted to know if another person was a mutation, they could access their records.

Second, while mutations can live relatively normal lives among regular humans, there are distinctive signs they are mutations. These things can be physical appearances, behaviors, and the like. For example, Birkin can pass off as a normal human most of the time and can control his other forms. However, he will instinctively transform if he feels threatened or if he's about to give birth (He shifts into his fifth form and goes into a trance). Likewise, there's also the risk of a mutation accidentally transferring their ailments to regular people. To put it bluntly, Charlie and Birkin couldn't do the deed (so to speak) without the risk of Birkin infecting her with the G-Virus.