10-year-old girl is the only person in the world with a genetic defect that sees her grow uncontrollably

A 10-year-old girl who is the only person in the world to suffer from a type of chromosomal abnormality has been described as a medical phenomenon.

Jessica Ruston, from Southport, was told she had the genetic defect - which has yet to be named - after being tested for another disorder.

Doctors also discovered she has Beckwith-Wiedemann syndrome, a rare uncontrollable growth condition that affects one in 14,000 children. 

It is believed her defect is fueling the growth and making it harder for her to receive effective treatment. 

However, because she suffers from scoliosis it is hard to tell just how tall she is as a result.

Her mother Alison, 37, said: 'Jessica doesn't follow a rule book – there are no other cases like her in the world.

'She's not a typical Beckwith-Wiedemann child, so it's difficult to know what's going to happen in the future.

'We just try to live each day and make the best of it.'

When Jessica was born a month early, she already weighed 8lb 5oz - heavier than the 5lb average of a baby at this age.

But within three days alarm days began to ring when she appeared to have jaundice and struggled to feed.

Concerned, Mrs Ruston and her husband Mark, 42, took their daughter back to hospital but doctors were baffled as to what was wrong.

For eight months the family travelled back and forth between various medical appointments.

Doctors referred the family to Alder Hey Children's Hospital in Liverpool. 

Here, they diagnosed Jessica with Beckwith-Wiedemann syndrome through a chromosome test.

A typical symptom of the condition is for babies to be born with their intestines outside the abdominal wall.

However, Jessica didn't have this - delaying the diagnosis.   

As a result of the condition, her tongue is so overgrown that it can block her airway. Surgeons were forced to perform a tracheostomy to help her breathe. 

While her bowel was so badly twisted when she was born meaning that she must be tube fed. 

The test also revealed she had the unique chromosome defect. 

However, despite her complex medical needs, Mrs Ruston said she is a bright, positive young girl. 

She added: 'She's just incredible. Though she can't speak, she has a way of holding a conversation through body language.

'People are just drawn to her. When strangers meet her, it's lovely. Quite often I just stand back and watch.

'She makes me smile and cry happy tears daily. She's the happiest and most determined person I've ever met.'

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