The results show that valproate is able to exert a direct effect on the activity of the human SMN gene, says Professor Wirth, but it is still unclear whether SMN expression in blood reflects SMN expression in motor neurons, and hence will have an effect on muscle strength. "These pilot studies have to be followed up by Phase II and III clinical trials in SMA patients," she said, "but unfortunately, there is very little interest from the pharmaceutical industry in clinical trials for rare disorders. However, the long-term outcome could be both improved therapy to enable a better quality of life for SMA patients, and also the introduction of neonatal screening so that therapy could be started before the first symptoms appear."
Another study involving valproate will be presented by Professor Aurora Pujol, of the Medical and Molecular Genetics Centre- IDIBELL and the Institució Catalana de Recerca i Estudis Avançats (the Catalan Research Agency) in Barcelona, Spain. Dr. Pujol and her team are trying to develop new therapies for X-linked adrenoleukodystrophy (X-ALD). This disease involves a single gene on the X chromosome (the ALD gene) and is the most common inherited single-gene disease involving damage to the myelin sheath, which insulates nerve cells in the brain.
Using a mouse model of the disease, Dr Pujol and colleagues found that a protein called ALDR (very similar to the ALD protein mutated in the disease) could, if over-expressed, compensate for the loss of the ALD protein and prevent the development of neurodegenerative symptoms. This striking prevention of the disease lasted during the whole 2 year life span of the mouse.
Source:European Society of Human Genetics