Your blood tests are normal. Your sleep is adequate. You're still exhausted. This is the most common presentation I see in clinic and the answer is almost never found on a Histone modificationdriven structural remodeling unleashes DNMT3B in DNA methylation Science Advances Do you suffer with fatigue, brain fog, mood swings, or trouble detoxing? These could be signs of an MTHFR gene mutation, which affects methylationa key process for energy, detoxification, brain function, and Methylation Profile Test Integrated Wellness Clinic Psychologists & Naturopaths Sunshine Coast, Brisbane & Gold Coast