Three primary cancer predisposition syndromes known as Constitutional mismatch repair deficiency (CMMRD), Li-Fraumeni syndrome (LFS) and Neurofibromatosis-1 (NF-1) are some of many CPS which increase susceptibility to pHGG as a subsequent somatic mutation can initiate the onset of disease. The gene discussed is CAD; the disease is Li-Fraumeni syndrome.