(CBS) UCLA researchers are using a gene therapy to restore the immune systems of children with so-called Bubble Boy disease.

If untreated, the disease can be deadly.

The Ainslie family has been dealing with a rare disease since their son was 11 months old.

“He started getting really bad cough, vomiting, throwing up,” Jessica Ainslie, Colton’s mother, says.

Five year old Colton has severe combined immunodeficiency or SCID, also known as Bubble Boy Disease.

He's missing a gene needed for his immune system to develop.

Kids with the condition are extremely vulnerable to viruses and bacteria and can die within one to two years if not treated.

Until now painful lifelong enzyme injections were the only option, but UCLA researchers are now using an experimental gene therapy with low dose chemotherapy.

“So take some bone marrow from the SCID baby and then in the laboratory add back to it a normal copy of the gene that they're missing that's causing SCID and then transplanting them back with their own bone marrow,” Dr. Donald Kohn from UCLA explains of the therapy.

Doctors estimate just 30 to 40 kids are born every year in the us with SCID.

There was a one in four chance Colton’s little sister Abigail would be born with the genetic disease. So the family had blood tests done right away. She had gene therapy treatment at just a few months old.

Her parents say you'd never know the 14 month old was sick.

“If they catch it earlier, they seem to do a lot better,” Jessica Ainslie says.

Colton is doing great and just started kindergarten.

“We're able to do whatever we want to do. We're not isolated in the house anymore,” Michael Ainslie says.

The Ainslie's hope this experimental treatment will help their children keep living normal lives.

At this point both children still need to take medications and have IV treatments to replace their antibodies to help fight infection.
New Gene Therapy For Children With 'Bubble Boy' Disease