Michael Jackson's Alleged Son -- POSITIVE DNA Match ... Or So They Sa

There's a 99.9% chance a 31-year-old man is Michael Jackson's illegitimate son ... at least that's the claim after an alleged DNA test turned up a match.

According to the test results -- obtained by Alki David and his company, FilmOn.com -- Brandon Howard is almost certainly Michael's son. David told TMZ Live he got MJ's dental impression from a Beverly Hills doctor that he got at an auction. The impression is 30 years old but David says its filled with DNA.

Brandon -- who now goes by B Howard and looks and acts very much like Michael -- was not present for the unveiling, but David says he had Howard's DNA and it matched up.

David would not say which lab performed the DNA test, but says it showed a clear match.

Brandon's mom -- Miki Howard -- is a famous gospel singer who Michael knew. She went by the name "Billy" back in 1982. Interestingly ... a year later Michael released "Billie Jean," which included the lyrics, "Billie Jean's not my lover" and "The kid is not my son."

For B Howard's part -- he's distancing himself from the whole spectacle, insisting he had nothing to do with it.