The concept of the gene in psychiatric genetics and its consequences for the concept of mental illness

At this point in time, it is hard to say which consequences for the concept of mental illness result from modern genetics. Current research projects are trying to find significant statistical correlations between the diagnosis of a disease and a gene locus or an endophenotype. Up until now, there has not been any identification of alleles or mutations causing mental illness. In the meantime, the relations between the genetic basis and the disease are given the term “genetic vulnerability” as a placeholder; this concept simplifies the complex relations between the DNA and even the simplest cell functions observed in modern genetics. According to complex gene models like the systemic theory of DNA, it will not be possible to identify the genetic factors without a precise knowledge of the factors which modulate the gene expression. The significance of genetics as part of the concept of mental illness will not be able to be defined without further progress in developmental biology and psychology. Currently, psychological theory fails to acknowledge the complexity of the relationship between the DNA and the environment. Some starting points from which to develop such an understanding can be received from “developmental studies” and studies of the “psychophylogenesis”. An interdisciplinary concept of the biological basis of the psyche is needed.