The mother of runaway teenager Donna Louise Healey today pleaded: "I need to know what has happened to my daughter".

Lorraine Wilkinson faces a month's wait to discover whether a mummified body dumped in Leeds 12 years ago is the 18-year-old who walked out of their Little Horton home three years earlier.

Experts are set to compare DNA from the corpse - discovered on pile of timber in an overgrown garden - with Mrs Wilkinson in order to prove or dispel a link.

Mrs Wilkinson, pictured with a photo of her long-lost daughter, said: "The chance that it is Donna is about 95 per cent. When the police came round and told us I just couldn't believe it. I had thought Donna had gone off and built herself a new life somewhere else but always expected that she would come back one day."

Mystery surrounds Donna's whereabouts between the time she walked out of their home in Roxby Street in 1988 to the time the body was found in 1991. She may have been living in Leeds at the time.

Police have appealed for information about her lifestyle and where she was staying.

Mrs Wilkinson, 58, said: "She took clothes and her records with her so she must have put them somewhere. I would just ask anyone who knows where she was staying to contact the police for our sake. We need to know what happened to our daughter."

She told how Donna had been a "lovely girl" but then got in with a bad crowd. "She was being the rebellious teenager at the time but we thought she would eventually grow out of it and come back. I always expected her to be walking through the door one day but now it doesn't look like that will happen."

She said life for her and Donna's step-father Keith Wilkinson, 60, had been a nightmare since her disappearance.

She told how the couple had driven around West Yorkshire hunting for her and had continued the search while on holiday believing she may have left the country.

She added: "There are so many questions left unanswered. I don't even know if she was alive to celebrate her 20th birthday."

She urged anyone with information to contact the police and added: "All we want is to settle this once and for all."

Detective Inspector Chris Binns said that if tests showed the body was not Donna, she remained a missing person. Anyone with information should call (01274) 376459.