Advanced paternal age has been associated with greater risk for psychiatric disorders, such as schizophrenia and autism. With an increase in paternal age, there is a greater frequency of certain types of mutations that contribute to these disorders in offspring. Mutations are changes in the genetic code. Recent research, however, looks beyond the genetic code to “epigenetic effects”, which do not involve changes in the genes themselves, but rather in how they are expressed to determine one’s characteristics. Such epigenetic changes in sperm, related to ageing, have been linked with psychiatric disorders in offspring.