It is becoming more common to have ANE patients and their families tested for a gene mutation. It is important to note, however, that even with the gene mutation, not all mutations will result in ANE. The actual trigger has yet to be determined. Probability of recurrence after the first episode, is 50% on trigger activation (ie. Influenza; HSV) and then 25% after a second episode. Note that triggers vary from one patient to the next. Some patients will only have 1 trigger while others will have multiple.At least three mutations in the RANBP2 gene have been found to increase the risk of developing acute necrotizing encephalopathy type 1 (ANE1). These mutations change single protein building blocks (amino acids) in the gene’s protein resulting in the production of a protein that cannot function properly. The mutations do not cause health issues on their own; it is not clear how they are involved in the process of a viral infection triggering neurological damage.