New DNA evidence has ruled that Lisa Jane Browne DID die of a rare heart abnormality which could now spark a fresh probe into her death.

The 27-year-old registered nurse died in January 1998 after being startled by her 6am alarm call.

Her family, from Connah's Quay, Deeside, North Wales, has always suspected she died as a result of the rare Long QT Syndrome, an electrical abnormality of the heart which cannot be detected after death.

And in light of the new evidence based on Lisa's post-mortem tissue, Cheshire coroner Nicholas Rheinberg may now be forced to order a new inquest into her death.

Last night, Lisa's mum Doreen Harley welcomed the new evidence after a two-year wait, saying it was the "final piece of the jigsaw".

She is calling for a fresh inquest into her daughter's death and wants Mr Rheinberg to strike out the original inquest verdict that her cause of death was "unascertainable".

Mrs Harley, 57, wants her daughter's death certificate to be re-written and her cause of death to be certified as a result of Long QT Syndrome.

She said: "We have been given this new evidence following DNA tests in Sweden. We have waited two years for this result which is based on DNA tests taken on Lisa's post-mortem tissue.

"We have been in contact with the Cheshire coroner to ask if he will consider opening a new inquest. We expected this ruling but it is the final piece of the jigsaw."

Lisa Browne was due to attend work as a nurse at the Countess of Chester Hospital on the morning of her death.

"It is now clear Lisa died as a result of this syndrome," said Mrs Harley. "I believe she died after she woke to turn her alarm off."

Although the DNA tests uphold what Mrs Harley always believed, the results could mean bad news for Lisa's five-year-old nephew Adam, who lives in Nuneaton.

Since Lisa's death, her family have all been screened. Her father Terry, sister Rachel, and nephew Jack have all been diagnosed with Long QT Syndrome.

The family will soon learn if Lisa's five-year-old nephew has the condition.

If he is diagnosed, Adam may have to endure a course of beta blockers to help regulate the heart or face the prospect of surgery to have a pace-maker-style machine fitted.

"We are waiting for the results of DNA tests to find out. We should hear very shortly," said Mrs Harley.

"There is a 50:50 chance he may have it."

Although he has been passed the new DNA evidence, Mr Rheinberg is awaiting the advice of Lisa Browne's pathologist at the Countess of Chester Hospital before deciding whether to open a new inquest.

If he chooses not to, he still has the power to amend Mrs Browne's cause of death on her death certificate.