Oct 29, 2007
Treatment for adrenoleukodystrophy has mainly involved bone marrow transplant, but this can be problematic due to lack of donors and rejection by the body.
French doctors have now managed to modify the boys' own bone marrow.
They unveiled their findings at a summit of the European Society of Gene and Cell Therapy in Rotterdam.
Adrenoleukodystrophy (ALD) is a rare inherited disorder that leads to progressive brain damage, failure of the adrenal gland and eventually death.
It occurs because a flawed gene on the child's X chromosome means his body cannot produce an enzyme needed to break down fatty acids which can accumulate in the brain.
There is no cure. "Lorenzo's Oil", a mixture of oleic acid and euric acid, is only really effective before the onset of symptoms.
A team led by Patrick Aubourg, a professor at the Saint Vincent de Paul Hospital in Paris, started to look at whether it was possible to correct the faulty gene.
They used a harmless version of HIV as a vector to carry a corrected version of the gene into the bone marrow cell.
HIV, which can lead to Aids, is the only virus known to be capable of carrying a gene into the nucleus of non-dividing cells, such as stem cells - the process needed if the treatment is to have a long-term effect.
The treated bone marrow was then reinjected back into the boys.
Results at both six months and a year suggested the production of the missing enzyme had noticeably improved.
"But we need to be cautious, especially as we need to know if it will be a sufficient and long term effect, and if no complications will arise due to the use of this vector," said Professor Aubourg.
But Paula Brazeal, the head of the United Leukodystrophy Foundation, said this was undoubtedly "the future".
"We've been waiting for this breakthrough for a long time. This is the way treatment is heading.
"Of course it's early days yet, but parents really can start to feel hopeful, even if more patience is needed."