Harry Potter author JK Rowling has said it is "painful" to know that her mother never knew about her writing success.
Rowling said she was beset with "guilt and worry and anxiety" when her mother Anne was diagnosed with multiple sclerosis, a disease which led to her death in 1990.
Speaking on Radio 4's Woman's House, she said she regretted her mother not being around to see the books become bestsellers.
"She never knew about Harry Potter - I started writing it six months before she died, so that is painful. I wish she'd known."
The Orkney Islands have the highest rate of multiple sclerosis in the world, University of Edinburgh scientists said.
Researchers found the rate for probable or definite cases of MS in the Orkneys is now 402 per 100,000 - up from a previous high of 309 per 100,000 in 1974.
Dr Jim Wilson, of the university's Centre for Population Health Sciences, said: "Our study shows that Orkney has the highest prevalence rate of MS recorded worldwide.
"These findings may reflect improved diagnostic methods, improved survival or rising incidence. We are trying to work out why it is so high, but it is at least partly to do with genes."
The study appears in the Journal of Neurology, Neurosurgery & Psychiatry.
Our research shows the transformative effect that alemtuzumab can have for people with MS.
Patients who continue to show disease activity while on their initial therapy are especially difficult to treat.
Now, we have shown that alemtuzumab works where first-line drugs have already failed.
It not only reduces the chances of disability associated with MS but may even result in long-term clinical improvements.
The multiple sclerosis study published in the journal The Lancet found that alemtuzumab significantly reduced the number of attacks or relapses by people with MS.
This result was seen both in patients who had not previously received any treatment and those who have continued to show disease activity while taking an existing treatment for MS.
In one trial with patients who had recently relapsed, new episodes were reduced by 49% more than that achieved by the current standard treatment.
Over a two-year period, 65% of patients on alemtuzumab compared with 47% of patients on interferon did not relapse.
A drug which is said to "reboot" the immune system has been shown to be an effective treatment for multiple sclerosis (MS), a study has found.
The results of the trials were so encouraging in reducing the number of attacks in those affected that the MS Society is campaigning for the drug to become available on the NHS.
The research showed that alemtuzumab significantly reduced the number of attacks or relapses by people with MS compared to the current drug interferon beta-1a which is known commercially as Rebif.
Jack Osbourne can be a role model for multiple sclerosis sufferers, MS survivor and advocate Nancy Davis told Daybreak this morning.
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A new study into the effect of cannabis on Multiple Sclerosis has concluded that it doesn't slow down the progression of the disease as has been claimed in the past.
The drug is prescribed to sufferers to relieve pain and muscle spams.
The report's author Professor John Zijicek says trials like this are rare:
The first UK research study into the medical benefits of cannabis on Multiple Scelrosis has shown there is no benefit.
However there were benefits for those at the lower end of the disability scale.
The CUPID (Cannabinoid Use in Progressive Inflammatory brain Disease) study was carried out by researchers from the Peninsula College of Medicine and Dentistry.
It enrolled nearly 500 people with MS from 27 centres around the UK, who were either given capsules containing the active ingredient of cannabis and some given a placebo.
Alison Smith, an MS sufferer took part in the trial: