So with the laboratory you can remove and add genitals and other parts. But how does one change the gender tag. So a male going through the laboratory and becoming female via genital changes and vice versa just changes their physical appearance but not the Information Tag. 

Is that even implemented?

https://itch.io/t/298861/bugissue-with-gender-change

This is fixed now, but outdated gender tags might persist on characters from before the latest build. 

As a slightly pricey but verified work-around, the tag will update and then stay accurate once you change their sex in the lab. For example: I had Herm characters that were still showing as Female until I removed and then restored one set of genitals.