My mother and aunt through marriage both have that vit-whatever skin situation and neither look like MJ. If he wasn’t bleaching, then he’s got one of the most severe and conveniently “consistent” case I’ve ever seen. I’m no expert, though.
The following website shows pictues of a little girl with vitiligo, with before, during, and after photos. Before her skin was consistently brown. during the disease, her face was mostly white with brown patches. After treatment to even out her skin tone, her skin is consistenly white, even on her neck and ears.
From the site: “Depigmentation is a treatment that involves fading the rest of the skin to match the white areas. This may be the best treatment for people who have Vitiligo Skin Disease over 50 percent of their body.”
http://effectivevitiligotreatment.blogspot.com/2008/05/vitiligo-skin-disease.html