Gene therapy experts say they have found a way to persuade cells to repair themselves.
Instead of replacing a faulty gene, the new approach harnesses the cells' own correctional mechanisms.
German researchers showed a drug could influence the way a gene behaved in patients with a debilitating genetic condition.
The research focussed on spinal muscular atrophy (SMA), a relatively common inherited disease, and the leading cause of death in infants, affecting about one in every 6,000 newborns.
Due to degeneration of the motor neurons in the spinal cord patients develop muscle weakness and atrophy of the legs, arms and trunk.
In patients with SMA the survival motor neuron gene (SMN1) is deleted, but they all carry a copy gene (SMN2).
However, this only produces about 10% of the correct protein which is insufficient to prevent the diseases.
The severity of the SMA is influenced by the number of SMN2 genes, which normally vary between one and four - the more copies there are the better the patient fares.
The researchers, from the Institute of Genetics at the University of Cologne investigated a drug called valproate, which is already used to treat epilepsy.
Lab tests had shown it could increase levels of the SMN protein by up to four times.
Valproate was also found to raise SMN levels in brain tissue.
The team first treated 10 parents of children with SMA with valproate for four months.
It was found that using the drug significantly increased SMN levels in blood.
Following this, 20 SMA patients were treated with valproate.
Seven showed increased SMN2 levels in their blood.