Leukodystrophies are inherited diseases that result from the pathological reduction of myelin, the dielectric material that insulates axons in the human brain. Children suffering from a leukodystrophy have substantial morbidity and mortality, with more than a third dying by age eight. Unfortunately, despite the fact that the incidence of these diseases is relatively high (at least 1 in 7,000 births), more than half of all leukodystrophy patients are never fully diagnosed – i.e. the inherited mutation at the root of their affliction remains unknown.In this research project, we are harnessing the power of next generation sequencing technology to identify novel gene variants that cause leukodystrophy, the first step required to develop treatments for this disease. To achieve this, we are currently in the process of sequencing the genomes and/or exomes (i.e. the subset of the genome that contains protein coding genes) of approximately 300 children affected by these illnesses and, where possible, their unaffected family members. In total we will be sequencing the exomes of over 1000 individuals in the next 12 months.