The parents of a five-year-old girl who has a rare and life-limiting genetic disorder have shared their story ahead of charity fundraiser Jeans for Genes Day next month.

Rowen Riddett, who lives in Shefford, has fanconi anaemia - a genetic disorder causing bone marrow failure and a predisposition to cancer.

After a smooth home birth, Rowen's parents - Sam and Toby, both 37 - realised their newborn daughter had a problem.

"It was clear she had trouble swallowing," said Sam.

"We quickly found out her food pipe wasn't connected - there was a dead end at the top and her stomach was connected to her lungs. It was horrendous to discover this, but at three days old she had surgery to connect it and that went well."

But doctors warned Sam and Toby the condition is often connected to genetic problems, so Rowen was referred to Addenbrooke's Hospital in Cambridge for tests.

Sam said: "Nothing was found, so we assumed it must just have been a quirk."

Rowen seemed to progress well and went on to eat pureed food with no trouble, but at nine months old developed café au lait marks - similar to birthmarks but fainter.

Sam said: "There was a big one spread across her back and down her arm. The GP reassured us it was just a birthmark, but I felt intuitively it wasn't right. I called our geneticist and said I had a funny feeling about it. I worried I was wasting her time, but she told me to send her a picture. She immediately phoned me back and told us to come in."

Sam and Toby subsequently discovered one of them has a definite FA gene and the other a likely one.

Sam said: "I was so naïve - I saw the word 'anaemia' in the letter and felt relieved. I thought it just meant she needed iron. It made sense, as I'd been saying to the GP for two years that Rowen was pale. Then I decided to Google FA and I went into meltdown.

"I read it would affect every cell in her body and could lead to shortened life expectancy. I was baking for the school bake sale that day and somehow still managed to make the cakes.

"Ruth, the geneticist, called early the next morning and I asked if there was anything we needed to do immediately. When she said we needed to tell the insurance company if we were going away anywhere, I realised it was really happening."

Tests eventually confirmed Rowen has FA. Sam said: "I was at work when I got the call and, although I already pretty much knew she had it, there was still a part of me thinking maybe it was a mistake - or not as bad as they thought. I broke down on the spot."

But Sam and Toby have felt well-supported by the medical team. Sam said: "The doctors have been brilliant and I feel so grateful we know she has it. If we had listened to the GP, we wouldn't have known there was anything wrong until Rowen got leukaemia. We're fortunate to be ahead of the game."

Rowen's platelet count has already begun to drop and she is likely to go into bone marrow failure between the ages of seven and eight.

Sam said: "She's on the register for a transplant match and the list for possible gene therapy trial at Great Ormond Street Hospital, and we'll know how many matches she has when we go for her next appointment. That information is important - if there are lots of matches we can wait but, if not, we need to explore other options such as "saviour sibling".

"People can drop off the register and, as only two per cent of the UK is registered to donate bone marrow or stem cells, there's a possibility of there not being a match.

"Even with a transplant, there's a 10 per cent risk it won't work, or she could even die because of it. And when you get past that, she still has a higher risk of cancer, so we will have to be very careful. I worry about the teen years, when I have less control over her - being near people who smoke, for example, could be dangerous for her."

But Sam knows there are reasons to be optimistic. "Life expectancy has gone from 11 to 35 since 1990, so it might go up more in another 10 years," she said.

And Rowen is an active, fun little girl. Sam said: "She's just learned to swim and ride a bike. She loves school and fights with her sister, Allegra."

Jeans for Genes Day runs from September 16 to 20, when people are invited to wear jeans to work or school in return for a donation to children's charity Genetic Disorders UK.

To sign up for your fundraising pack, visit jeansforgenesday.org.