Researchers at A*STAR’s Singapore Institute of Manufacturing Technology (SIMTech) and the Singapore Centre for 3D Printing (SC3DP) at Nanyang Technological University have developed a way to create pigmentation in 3D printed skin by using bioprinting to control the distribution of melanin-producing skin cells, on a biomimetic tissue substrate. They used three different types of skin cells and drop on demand method of bioprinting to create the pigmented skin.

Source: https://phys.org/news/2018-01-human-skin-pigmentation-recreatedwith-d.html