The Challenges of Genetic Tests for Human Behavior
Gershon, Elliot S., The Israel Journal of Psychiatry and Related Sciences
Abstract: Objective: To review the potential benefits and adverse effects of genetic tests that may develop, that effectively predict mental illness or variation from the norm on behavior traits. Method: A review is offered of the history of genetic-based political policies and racial discrimination. The current status of genetic research in mental disorders is described. Anticipated genetic progress, and derivative tests and limits on their predictive power are considered. Results: There does exist a potential for invidious stigmatization and discrimination, based on genotypes of individuals and allele frequencies in communities, in various transactions such as health care access, employment and education, as well as in more intimate decisions including choice of spouse and decisions to become a parent. Conclusions: The major uses of valid genetic tests for human behavioral traits will be for development of knowledge on pathophysiology of illness, and for development of new treatment and educational strategies to deal with illness. Some extension of genetic tests into predictions about specific individuals may well occur. Awareness of the potential for discrimination, and a determination to develop culturally sensitive and fair applications of genetic tests, is required to avoid adverse effects on individuals and communities.
Genetic tests for susceptibility to mental disorders, and for variation in normal mental functioning, have begun to be technically feasible (such as APOE4 as a test for susceptibility to Alzheimer's disease), and we may confidently expect more of these genes to be identified in the coming years. However, genetic tests of this kind will not easily pass into widespread use, because of the challenges they present. First, from a clinical viewpoint, particularly when there is no connection between knowledge of susceptibility and treatment or prevention, there is no consensus that there is any benefit to having susceptibility test information about a person, especially one who has never shown signs of illness. Also, there is the historical context of human genetics, and persisting controversies over genetics and human behavior, leading to concerns over individual and communal stigmatization. Furthermore, the meaning of genotype information in an individual's self-concept needs to be further explored. Genetic test results may generate significant narcissistic injury, and this will undoubtedly generate a great deal of inquiry and be explored in many individual psychotherapies.
The Historical Context
Sir Francis Galton (1822-1911) is historically the founder of behavioral genetics as a scientific discipline, but he is also the founder of eugenics, a political and social movement that embodied the racial prejudices of his times and gave them a cloak of scientific respectability (1, 2). Eugenics (usually translated as race improvement or racial hygiene) is a term introduced by Galton in 1883, and launched by him as a formal political movement in 1901. Its scientific basis is pre-Mendelian genetics, when inherited characteristics were not thought to sort independently. Rather, there was a 19th century animal breeder's view of heredity - an individual has more or less of the ideal characteristics of its breed (or its human race). Darwin's concepts of evolution were incorporated into this system of thought- human races were shaped by natural selection to be superior or inferior. Superior races are advanced; inferior races are primitive, ape-like and child-like. Eugenics was seen as improvement of the superior race (not coincidentally, the race to which Galton belonged). Positive eugenics was encouragement of superior individuals of the [superior) race to mate together and breed. Negative eugenics was elimination of undesirable traits and inherited diseases, especially the feebleminded and insane, from the [superior] race, by preventing reproduction.
As an example of an application of this system of thought, the following appears in a then reputable human genetics textbook published in New York in 1931, as a translation from the German edition of 1927:
In any case, there are close relationships between race and crime. …