Neurogenetics is the field of study that investigates the role of genes in the development and function of the brain and nervous system. Every one of us carries a 3 billion letter instruction booklet in every cell in our body. These letters code for 25,000 genes, which play an incredibly important role in how we develop, our physical features and our behaviour. If the DNA molecules from all of our cells were joined together they would stretch around the solar system two times. The genetic code needs to be copied every time a new cell is formed, and not surprisingly this process can be error prone. Most commonly, these errors do not have any significant effect-they are what is called silent variation. Less commonly, the errors can affect the function of the cell, but not in a detrimental way. For example, differences in eye colour or blood type represent neutral variation. However, in a small percentage of cases these errors or mutations can have a significant effect on how a cell functions, with detrimental outcomes.

Identifying the specific error that has occurred in someone’s genetic code is an essential step in understanding the underlying cause of a disorder and being able to develop meaningful pharmacological or physical therapies to reduce or eliminate the associated symptoms. The goal of ‘genomic medicine’ is to be able to tailor a treatment specifically to each individual. Until relatively recently, it was incredibly difficult to pinpoint a genetic mutation in a person. What has changed in the last decade has been the development of powerful sequencing technologies and computational platforms to read all 3 billion letters of the code. The reading of a person’s genetic code, termed their genome sequence, is now becoming much more accessible in both research and diagnostic medicine. While completion of the first genome sequence took 13 years and cost one billion dollars, such a project now takes about 2 days and costs ~$2000 Australian dollars. Ironically, researchers such as myself are now overwhelmed with data. Previously we had limited information about an individual’s genetic code and sequencing was very time consuming. Now we can rapidly read the code but find it hard to interpret the results. Typically, an individual genome will have over 10,000 changes in the code that are either very rare or unique to that individual.

The challenge for researchers now is to sift through these changes and try to identify the specific one that is causing the disease. We accomplish this using different models and assays of a gene’s function. Often studying additional family members can also help to identify a disease causing mutation, providing better understanding of the disease process.

So, what does this mean in the context of Disorders of the Corpus Callosum? Until very recently we knew very little about the role of specific genes in the formation and function of the corpus callosum. We and others have recently identified genes that are clearly important in this process, providing new insights into the processes involved and hope for future development of therapies that may be of clinical benefit. Of more immediate value is the utility of a genetic diagnosis to provide individuals and families important information about the cause of the disorder and potential severity and trajectory. I look forward to continuing my research in this area and sharing the outcomes with the AusDoCC community, I thank the committee and entire support group for the opportunity.