A woman who has young onset dementia has spoken of her heartbreak following the death of her mother to the disease.

At the age of 26, Sophie Leggett from Lowestoft was told there was a genetic link to young onset Alzheimer's in her family.

She discovered she had a 50pc chance of carrying a rare genetic mutation, which causes middle-aged Alzheimer's. Symptoms tend to develop in the 30s or 40s.

'I had a complete meltdown. I was 26 at the time and my daughter was two years old.

'It was just too painful to contemplate that not only I could be affected but my daughter too. I chose to bury my head in the sand,' the 42-year-old said.

Her mother and aunt both developed symptoms in their 40s and died just years later.

By that time, some of Mrs Leggett's cousins had also developed the symptoms.

Following her mother's death in 2012, she started to research and donated her mother's brain the Dementia Research Centre.

Since then, she has taken part in observational student research at the centre which involved cognitive tests, scans and lumbar punctures.

After a year of genetic testing, she found out she had the mutation and will develop the symptoms.

She said: 'Now I know what is going to happen to me I find it easier to look to the near future.

'I make sure that I fill my days with fun things and surround myself with people who make me happy.

'I don't waste time on things or people that I don't like. I have also been able to make my wishes known, make a will and I plan to donate my brain for research when I die.

'I still have a life to live and I make sure I enjoy it.

'It was very difficult for my husband and my daughter but we have come to terms with it as a family,' she said.

She will run the London Marathon on April 28 to raise money for the National Brain Appeal charity.