sentence1: NEW YORK (CBS) ―  Imagine developing a condition where you start to lose the color in your skin. It's called "vitiligo" and it affects millions of people in this country.  If you remember the King of Pop from his "Thriller" days, you might notice that his skin tone was what you would expect for an African-American. Today? Michael Jackson is as pale and milky white as a ghost.  What happened is he developed the skin condition, vitiligo, reports CBS station WCBS-TV.
sentence2: Jackson's skin has become lighter because of vitiligo.