The cause of Braf gene mutation is not exact, it may be related to environmental factors, genetic factors, viral and bacterial infections and other factors. 1. Environmental factors can lead to gene mutation, such as atmospheric pollution, chemical pollution, rays and so on, which are common triggers for the development of malignant tumors. 2. Genetic factors are also the cause of Braf gene mutation, so people with family history should pay attention to the screening of malignant tumors on time, and strive to achieve early detection and early treatment. 3. Viral and bacterial infections may also lead to the occurrence of Braf gene mutation, and the correlation between infections and malignant tumors has been clinically proven. Since the cause of Braf gene mutation is not exact, it is often thought to be caused by multiple factors, so it is difficult to prevent it completely.