An Ipswich man will be running the London Marathon this year in memory of the father he never knew.

Jack Shepherd, 31, was conceived through a sperm donor but grew up unaware of how he had been conceived.

"I had the perfect upbringing," said Mr Shepherd.

"Everything was really good."

It was only while his parents were getting divorced that Mr Shepherd found out about his birth.

His parents had gone to Harley Street in London to have IVF to have both Mr Shepherd and his older brother, both of whom were conceived using donor sperm.

"It was pretty shocking," said Mr Shepherd.

"I felt like my life had flipped on its head."

After taking some time to process the news, Mr Shepherd decided he wanted to find out who his father was.

"It was kind of an identity crisis," said Mr Shepherd.

"I struggled with it."

Ipswich Star: Jason Shepherd died at age 22Jason Shepherd died at age 22 (Image: Jack Shepherd)

With the support of his mother he set about looking for his father, but rules at the time meant donors could remain completely anonymous and the clinic in London was unable to help.

"I really did feel like I had hit a brick wall," said Mr Shepherd.

Fortunately Mr Shepherd was given the details of a charity that helps donors and those conceived by them to find each other, called Donor Link.

Mr Shepherd was told the likelihood of finding a match within their database was low.

A few months later they found a match, Mr Shepherd's dad, Jason.

Sadly, Jason had died not long after Mr Shepherd had been born, at the age of 22.

However, his parents, Mr Shepherd's grandparents were still alive and eager to meet him.

After months of correspondence they met in person.

"I remember reaching my hand out, knocking on the door once and the door flew open immediately and this little old lady embraced me in a big hug," said Mr Shepherd.

"I've gained grandparents out of this, an uncle and cousins."

Mr Shepherd was told that Jason had died in 1990 very suddenly from a heart condition known as sudden arrhythmic death syndrome.

The condition can be inherited and so Mr Shepherd now receives regular check ups to ensure that his heart remains healthy.

As a fitness enthusiast Mr Shepherd has been putting his talents to good use with fundraising efforts in recent months.

Ipswich Star: Jack Shepherd found out that he was conceived via sperm donorJack Shepherd found out that he was conceived via sperm donor (Image: Jack Shepherd)

At the start of March he ran four miles every four hours over 48 hours in what is known as the David Goggins Challenge to raise money for charity.

"The response I had was unbelievable," said Mr Shepherd.

His efforts in the challenge, along with some help from his grandmother, attracted the attention of the British Heart Foundation who have given him a spot on their London Marathon team for this year.

It's a dream come true for Mr Shepherd who has tried for many years to get a space to run the race.

"I was just completely blown away," said Mr Shepherd.

"I think it's the biggest buzz I've had in years."

So far Mr Shepherd has raised £2700 and is continuing to fundraise ahead of the marathon in October and has further events to run in including the Great East Run and the Great North Run.

You can donate here.