Our genome contains many small variations and abnormalities that may play a crucial role in the development of various diseases, including cancer. Cancer is a complex disease where both environmental and genetic factors interact to influence disease risk and progression. One third of all childhood cancers are brain tumors, which represent one of the leading causes of cancer-related morbidity and mortality in children. Gliomas, a common type of brain tumor in children, have been linked to genetic alterations in the genome—particularly within a region on chromosome 9. Although certain genetic changes in this region have been identified and appear to be associated with an increased risk of glioma, the exact mechanisms underlying this connection remain poorly understood. Similarly, genetic variants in the same region on chromosome 9 have been associated with > 20 types of cancer in adults. To understand the role of this region on chromosome 9 in cancer development, further research is essential. This project aims to map and analyze genetic aberrations on chromosome 9, with a primary focus on how these changes may influence the risk of developing brain tumors in children. The study will use data from pediatric cancer registries and biobanks, including DNA samples from both blood and tumor tissue collected from children diagnosed with glioma. To gain a more detailed view of the genetic alterations, we will employ cutting-edge genomic technologies such as long-read sequencing. This method allows for the detection of complex genetic changes that are difficult to identify using traditional techniques and may provide new insights into the genetic mechanisms driving cancer development. By identifying specific genetic variants linked to an increased risk of pediatric gliomas, it enables healthcare providers an early identification of individuals at higher risk of developing the disease. Early detection may lead to more effective ways to prevent and treat these tumors, and the long-term goal of the project is therefore to improve diagnosis and treatment, which can lead to better survival rates and quality of life for affected children. The identification of these variants may also support genetic counselling, helping families better understand inherited risks and make informed decisions about monitoring and care. Additionally, this research may contribute to the development of precision medicine for acquired structural variants or tissue-specific microsatellites, allowing treatments to be tailored based on individual tumor genetic profiles. The results from this project could pave the way for structural genetic variants in pediatric gliomas to be incorporated into routine diagnostics as cancer biomarkers in healthcare. These genetic markers have the potential to aid in early detection and diagnostic classification, improving genetic counselling and enabling earlier treatment interventions for this group of disease.