Transgenic

Genetically modified mammals, or Transgenics, are mammals that have been genetically engineered. They are an important category of genetically modified organisms. The majority of research involving genetically modified mammals involves mice with attempts to produce knockout animals in other mammalian species limited by the inability to derive and stably culture embryonic stem cells.

In Deus Ex and Deus Ex: Invisible War
In both games transgenic creatures are created by VersaLife under the Genetically Modified Organism Project, which breeds creatures such as Greasels and Karkians. Both organisms appear to be recombinant creations. A third major project, Grays, are supposedly cloned from DNA recovered from Roswell--though they are also suggested to be engineered monkeys (such as RUCK) which no hair and spit toxic substance. After the Collapse, some of the creatures have escaped from the nearby VersaLife lab.