'Losing my sight felt like a ticking time bomb'

A man, who is taking on an SAS mountain challenge, says it felt like "a ticking time bomb" when he found out he would lose his eye sight due to a rare genetic disorder.

Mark Long, from Paulton in Somerset, was told he could become blind by the age of 16 after he was diagnosed with retinitis pigmentosa following a routine eye exam aged 12.

Long, who uses a guide dog, said he did not have vision loss until his 40s and now only has limited vision in his right eye.

Raising money for the Guide Dogs charity in his Pounds for Penny campaign, Long is set to run the 15-mile (24km) SAS "Fan Dance" route on Pen y Fan in Wales.

The SAS Fan Dance mirrors the UK Special Forces selection test and is suitable for experienced hikers with high fitness levels.

"I constantly tried to pretend I was okay. [But] It was a ticking timebomb," Long said.

"Into my late 30s I used to drive until I smashed my truck to bits and that right there was the moment I needed to admit something was not quite right.

"I needed to have some form of acceptance," he added.

He said he eventually lost "any useful vision" in his left eye after his 40th birthday and his right eye was now "getting worse".

Long now gets support from his black Labrador guide dog called Mary, thanks to the Guide Dogs Charity.

"People don't understand that Guide Dogs is solely powered by peoples generosity," he added.

Long explained there was no cure for his condition and wants to "get out there and talk" about it.

"Sharing is the best way of getting through it," he said.

"Fortunately for me, I managed to get to my 40s, I've seen a lot of cool stuff and I got to see my daughters face - I got to see things that have been quite rewarding."

Long aims to raise £102,000 for Guide Dogs UK - the cost of funding a guide dog for its entire lifetime.

Pam Gratton, community fundraising manager at Guide Dogs, said what he has achieved so far is "amazing".

"It's a tough challenge.

"We're hoping to have a big turnout of people there to support him."

Long will take on the Pen Y Fan challenge on 2 May.

The condition means the millions of light sensitive cells at the back of my eye are gradually dying.

There is currently no cure - just one approved genetic therapy that can stop the disease progressing, but only for some patients with a specific faulty gene.

According to Retina UK, it is an inherited condition and is typically diagnosed in young adulthood, but the age of onset may range from childhood to late adulthood.

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