Genetically modified humans are available to play as futuristic characters only. With their advanced technology, humans have been able to alter their genetic structure to incorporate features found in other earth creatures, for example, cephalopod-like (eg, octopus) colour-changing abilities, retractable claws, etc. They have also invented other genetic mods. Such humans are rare, as genmodding is expensive, borderline illegal, and difficult. No one can be genetically modified -after- their birth, this is something that must be done to create a specific result at an embryonic stage. Genmods that might be common would be increased resistance to disease, or increased self-healing capacity, that may have been applied to whole populations.
If playing a genmod, please consider why and how they came to be, and the purpose of the mods.