A Camden teacher is to cycle 1,200 miles to find a cure for his daughter's debilitating "sleeping beauty" illness.

David Aronsohn, a history of art teacher at Camden School for Girls, is using his summer holiday to cycle from Land’s End to John O’Groats.

His daughter has Kleine Levin syndrome (KLS), a very rare, incurable disorder, also known as "sleeping beauty" syndrome, that only one in a million people around the world suffer with.

A young woman now in her 20s, his daughter may sleep for weeks or months, with no recollection of time spent.

"She's on her 11th episode and had it for seven years now.

"When she first got it at 16 it wasn't a big problem and now it is," David said.

"At first she'd have it for two weeks and she'd say: 'What's this?' She couldn't believe it was a real illness. But in the last couple of years she's been getting it for four to six months."

David said it's known as a "de-realised state". "

You don't make sense, and often, in my daughter's case, your voice changes from a young woman to that of a seven-year-old child.

"Your mind doesn't work properly, you sleep a lot and supposedly you're when you're awake you are actually asleep, which doesn't make any sense.

"It's like an epileptic fit in that you get a bit of a warning, you know it's going to happen, you feel weird, then once you're in an episode, that's it. You're gone.

"They think it's genetic, they don't know why it starts, they know it stops after about 10 years and there's no way of measuring it as not many people have it."

The 58-year-old said it is often mis-diagnosed as bi-polar but said the health issue is closer to a "neurological malfunction".

"My daughter once had it for two months and had missed Christmas and friends' parties. When she woke up she wasn't aware two months had gone."

HIs daughter said "it's a sleep filled with nightmares" with "very little memory of what happened".

"You know you are going to lose yourself and your life as you know it for a while but without knowing how long until you get it all back," she added.

David said any money raised will go to to KLS Support UK, The KLS Foundation and a research centre in America.

To donate visit www.justgiving.com/fundraising/klsljogdavid-alice