It looks highly unlikely. However according to Joe Jackson, he claims Omer Bhatti is the missing link. Judge for yourselves...
Here's My Assessment
Since Michael has not lost his virginity until he got married to Elvis Presley's daughter, there's no way he could be Michael's son(unless artificial insemination is considered).
Through the 90's, Omer and Michael were this close and did a lot of things together as friends. He idolized Michael so much that he dressed and imitated the King of Pop. But those claims arn't good enough as you need to look at the whole Jackson ancestry picture(not to mention mingling Omer's family genes in there). Plus, we'll need to venture back to Michael's Off The Wall Era(before he broke his nose on the set of The Wiz) to make an accurate assessment of Michael Jackson's features.
Since Omer and even Michael himself denied the rumors, I'll just leave it at that.