Ever wondered how Ozzy Osbourne survived all those years of substance abuse? According to a scientist, it’s due to a genetic mutation.

In a book called Pleased to Meet Me: Genes, Germs and the Curious Forces that Make Us Who We Are, scientist Bill Sullivan writes that Ozzy is “indeed a genetic mutant.” The book claims that Knome, Inc. studied Osbourne’s DNA in 2010 and determined that not only is he genetically predisposed towards addiction, but he also has a unique mutation which allows him to drink in larger-than-normal quantities.

Read the full story on Ultimate Classic Rock.