22 June 2009
ByAppeared in BioNews 513
Neuroblastoma, a form of paediatric cancer which affects the nervous system, may be caused by copy number variations (CNVs) in genes which control nervous system development. The research, published last week in Nature, suggests a different genetic mechanism for cancers than was previously proposed. Dr John Maris who led the study at the University of Pennsylvania, Philadelphia, US, said 'We can infer that it's not just going to be true for neuroblastoma. My expectation is that there will be many reports following on this of similar types of associations in other cancers.'
Neuroblastoma is the second most common form of cancer in children and is fatal in about two thirds of all cases. The study is the first to link any cancer to CNVs rather than to irregularities in the sequence of the genetic code: CNVs are additional or missing bits of gene, rather than 'mis-spellings' of genes. Dr Maris and his team had previously identified two genes which were linked to childrens' susceptibility to neuroblastoma, and report a third gene in this latest study. It is within the third of these genes (called NBPF23) that presence of CNVs is said to increase a child's susceptibility to neuroblastoma. 'This is a brand new area', said Dr Maris, 'we never suspected that this family of genes played a role in neuroblastoma.'
The team's conclusions were based on a study of DNA samples from 803 healthy children and 846 neuroblastoma patients. The results showed that the children with neuroblastoma children were much more likely to have CNVs in NBPF23 than the healthy children.
Although there are presently no obvious therapeutic applications of these findings, this work is another step in the direction of better understanding of neuroblastoma, and perhaps other forms of cancer too. Dr Maris said 'Only two years ago we had very little idea of what causes neuroblastoma. Now we have unlocked a lot of the mystery of why neuroblastoma arises in some children and not in others'.