Disclosed are materials and methods for creating customizable traits in animals. In the demonstration of the principle of the subject invention, a keratin- 14 specific promoter is used with, red fluorescent protein in the loxp cassette, dominant black (ΔG23 ) beta defensin 103 in the pigment cassette, and an SV40 (with intron) polyadenylation sequence. When Cre recombinase (or HTNCre) is applied to the animal's skin in a carrier base (e.g., lipid bilayers), fur is permanently genetically modified to turn black in the shape in which it was applied.
