Sharon Osbourne is ''terrified'' she'll die from Alzheimer's disease.

The 62-year-old star has revealed she and husband Ozzy Osbourne underwent a genome test and found that she has two of the four genes responsible for developing the debilitating disease.

She said: ''Ozzy and I had these tests done at a university in England, and the results took three months to come back.

''They test every single cell, chromosome and gene in your body; it's like a DNA test but a million times more sophisticated.

''The results show I have two of the four genes that give it to you. They're not the two major genes, but they're still there and I have them.''

The former 'X Factor' judge's music mogul father Don Arden passed away aged 81 in 2007 after battling the devastating form of dementia and Sharon - who has children Kelly, Jack and Aimee with Ozzy - admits she feels powerless in stopping the same from happening to her.

She told the Daily Mirror newspaper: ''I was terrified because my dad died from Alzheimer's.

''It is the most soul-destroying disease. To see someone you love come down with it... it's wicked, it really is.

''There is nothing I can do to prevent it, nothing. People say take cod liver oil and do puzzles and thing, but then I look at people diagnosed with dementia.

''My father was super active mentally, and take Margaret Thatcher, Ronald Reagan... they were all so active, and that's what really frightens me.''