A FAMILY who launched a worldwide search for someone with the right blood to save their baby boy have called on people to register as potential donors.

Andrew and Judy Kim's son Alastair was diagnosed with ultra-rare genetic disease chronic granulomatous disorder in February 2016.

The life-threatening condition wipes out his immune system, meaning even the tiniest infections leave him seriously ill.

Ally, who is now three, was selected as one of the first participants in a global gene replacement therapy trial at Great Ormond Street which will help him fight infections, but his only hope of a permanent cure is a bone marrow stem cell donor – and it will need to be a 90 per cent genetic match.

The search for Ally's donor is made even more difficult because of his ethnicity: Mr and Mrs Kim are both of Korean descent so a matching donor will most likely be of Korean, Japanese or Chinese heritage, but the number of East Asians on international donor registers is tiny.

As they continue their quest, the family, who live near Longworth with their other son Micah, six, urged people in Oxford to register as a potential blood stem cell donor and go on standby to save the life of someone with blood cancer or a blood disorder.

Mr Kim, a scientist and lecturer at Oxford University and Diamond Light Source in Harwell, said: "Ally has been doing well since he was discharged from hospital: he’s becoming more stable and his immune function slowly improving.

"He is on heavy medication and needs regular blood transfusions but it has been a huge step forward in recovery.

"As this is very much an experimental treatment we’re continuing the search for a matching donor as Ally might need a transplant in the future.

"We want to encourage people to register as a potential lifesaver to help give others a second chance of life."

One of the most common conditions in the UK requiring a blood transfusion is blood cancer, such as leukaemia.

A blood stem cell donation from a genetically similar person can often be the best hope of survival, but only one in three people in need of a transplant will find a matching donor in their own family.

More than 300,000 people in the UK are registered as potential donors with blood charity DKMS, but as few as five per cent of donors have a South Asian heritage and less than three per cent of donors are black – making it especially hard to find matching donors for people with a blood cancer from these ethnicities.

The Kim family is supporting the charity’s latest advertising campaign encourages people to 'swab to be a lifesaver'.

Mrs Kim said: "Thank you to everyone who has helped us spread awareness, registering as potential donor and all your love and support. We can never thank you enough."

But, she went on: "The need for more Asian donors is huge. Someone registering as a potential blood stem cell donor could have such a tremendous impact for people with a blood cancer or blood disorder. Please take the time to register."

Anyone aged 17-55 and in general good health can register a your home swab kit at dkms.org.uk.

To register one potential blood stem cell donor it costs approximately £40.