An epigenome is a chemical modification pattern of genomic DNA that determines the on/off status of genes, and its abnormalities are known to cause congenital diseases. Recent studies have shown that epigenomic patterns are altered by various environmental factors, indicating that epigenomic abnormalities also cause acquired mental and neurological diseases. An epigenomic pattern that reflects past environmental insults is an epigenomic signature. Therefore, it will be used as a marker for preemptive medicine in that it is not based on the population but is instead based on individuals.