Many cases of gene‐environment interaction, or , are misconstrued as evincing a genetic predisposition. I diagnose this misconstrual and then introduce a new concept— interactive predisposition —to correct for the mistake. I conclude by examining how recent debates over screening for individual predispositions are related to older debates about group differences between populations , drawing on the lessons of the latter to inform the former. †To contact the author, please write to: Department of Philosophy, University of Utah, Salt Lake City, (...) UT 84112; e‐mail: [email protected]. (shrink)

In a widely acclaimed study from 2002, researchers found a case of gene-environment interaction for a gene controlling neuroenzymatic activity (low vs. high), exposure to childhood maltreatment, and antisocial personality disorder (ASPD). Cases of gene-environment interaction are generally characterized as evincing a genetic predisposition; for example, individuals with low neuroenzymatic activity are generally characterized as having a genetic predisposition to ASPD. I first argue that the concept of a genetic predisposition fundamentally misconstrues these cases of gene-environment interaction. This misconstrual will (...) be diagnosed, and then a new concept—interactive predisposition—will be introduced. I then show how this conceptual shift reconfigures old questions and raises new questions for genetic screening. Attempts to screen embryos or fetuses for the gene associated with low neuroenzymatic activity with an eye towards selecting against the low-activity variant fall prey to the myth of pre-environmental prediction; attempts to screen newborns for the gene associated with low neuroenzymatic activity with an eye towards early intervention will have to face the interventionist’s dilemma. (shrink)

Pre-natal genetic enhancement affords us unprecedented capacity to shape our skills, talents, appearance and perhaps subsequently the quality of our lives in terms of overall happiness, success and wellbeing. Despite its powerful appeal, some have raised important and equally persuasive concerns against genetic enhancement. Sandel has argued that compassion and humility, themselves grounded in the unpredictability of talents and skills, would be lost. Habermas has argued that genetically altered individuals will see their lives as dictated by their parents’ design and (...) therefore will not acquire an appropriate self-understanding. How should we view enhancement efforts in light of these concerns? I propose that we begin by adopting a defeasibility stance. That is, I ask whether our belief that genetic enhancements serve in the best interests of the child is reason to genetically enhance, underscoring a sort of epistemic vulnerability. I utilize the epistemological notions of defeasible reasons, undercutting and overriding defeaters in order to better understand and systematically evaluate the force of such concerns. I argue that close examination of both objections using this framework shows that we have reason to enhance, a reason that is defeasible but as yet, undefeated. (shrink)

Many psychometricians and behavioral geneticists believe that high heritability of IQ test scores within racial groups coupled with environmental hypotheses failing to account for the differences between the mean scores for groups lends plausibility to explanations of mean differences in terms of genetic factors. I show that heritability estimates and the statistical analysis of variance on which they are based have limited relevance in exposing genetic and environmental factors operating within any single group or population. I begin with agricultural investigations, (...) where replication of genetic types and control over environmental factors are possible, and highlight the difficulties of moving from AOV of observed traits to investigation of measurable genetic factors. The difficulties can only be exacerbated for human data sets, which are equivalent to a crop trial in which each variety is replicated in only one or two of the locations. (shrink)

In a near-future world of bionics and biotechnology, the main ethical and political issue will be the definition of who we are. Could biomedical enhancements transform us to such an extent that we would be other than human? Habermas argues that any genetic enhancement intervention that could potentially alter ‘human nature’ should be morally prohibited since it alters the child’s nature or the very essence that makes the child who he is. This practice also commits the child to a specific (...) life project or, in any case, it puts specific restrictions on his freedom to choose a life of his own. Ultimately, genetic enhancement jeopardizes the very foundations of moral equality. I contend that Habermas’ argument is based either on a series of presuppositions that imply a gross misunderstanding of evolution or the relevant factual information cocerning the action we are about to morally assess is not empirically supported. Hence, the argument from human nature is based on a series of false or problematic assumptions, and, as such, it fails to play the normative role intended by Habermas. (shrink)

In this consensus report by a diverse group of academics who conduct and/or are concerned about social and behavioral genomics (SBG) research, the authors recount the often‐ugly history of scientific attempts to understand the genetic contributions to human behaviors and social outcomes. They then describe what the current science—including genomewide association studies and polygenic indexes—can and cannot tell us, as well as its risks and potential benefits. They conclude with a discussion of responsible behavior in the context of SBG research. (...) SBG research that compares individuals within a group according to a “sensitive” phenotype requires extra attention to responsible conduct and to responsible communication about the research and its findings. SBG research (1) on sensitive phenotypes that (2) compares two or more groups defined by (a) race, (b) ethnicity, or (c) genetic ancestry (where genetic ancestry could easily be misunderstood as race or ethnicity) requires a compelling justification to be conducted, funded, or published. All authors agree that this justification at least requires a convincing argument that a study's design could yield scientifically valid results; some authors would additionally require the study to have a socially favorable risk‐benefit profile. (shrink)

In Italy, a judge reduced the sentence of a defendant by 1 year in response to evidence for a genetic predisposition to violence. The best characterized of these genetic differences, those in the monoamine oxidase A (MAOA), were cited as especially relevant. Several months previously in the USA, MAOA data contributed to a jury reducing charges from 1st degree murder (a capital offence) to voluntary manslaughter. Is there a rational basis for this type of use of MAOA evidence in criminal (...) court? This paper will review in context recent work on the MAOA gene–environment interaction in predisposing individuals to violence and address the relevance of such findings to murder trials. Interestingly, the MAOA genetic variants impact future violence and aggression only when combined with the adverse environmental stimuli of childhood maltreatment. Thus nature and nurture interact to determine the individual’s risk. Based on current evidence, I argue there is a weak case for mitigation. But should future experiments confirm the hypothesis that individual differences in impulse control and response to provocation found in MAOA-L men (without abuse) are significantly magnified when combined with childhood maltreatment, the case could turn into a stronger one. (shrink)

This study is a contribution to the bioethical debate about new and possibly emerging reproductive technologies. Its point of departure is the intuition, which many people seem to share, that using such technologies to select non-disease traits – like sex and emotional stability - in yet unborn children is morally problematic, at least more so than using the technologies to avoid giving birth to children with severe genetic diseases, or attempting to shape the non-disease traits of already existing children by (...) environmental means, like education. The study employs philosophical analysis for the purpose of making this intuition intelligible and judging whether it is justified. Different ways in which the moral problems posed by reproductive technologies are often framed in bioethical debates are criticised as inadequate for this task. In particular, it is argued that the intuition cannot fully be made sense of in terms of harm to the children that such technologies help create. The study attempts to elaborate an alternative to that broadly consequentialist approach, by drawing on Martin Heidegger’s philosophy of technology, Hans Jonas’s ethics, and Aristotle’s practical philosophy, as it has been received and developed in the hermeneutical tradition. It is suggested that reproductive choices, unlike decisions for already born children, are characterised by a peculiar one-sidedness: the future child appears to the parents as something wholly theirs to decide about, not as a concrete other with whom they must interact in a responsive and attuned way. This is problematic because it means that such choices cannot call upon the particularised moral understanding only gained in interpersonal encounters. In particular, it makes them easily shaped by various tendencies, to which parents are always susceptible, to relate to children in instrumentalising ways, and at risk of reinforcing such tendencies. However, this does not mean that all uses of reproductive technologies are equally troubling. When selecting against severe disease the parents can rely on a widely shared illness experience to escape the dangers that one-sidedness involves. It is concluded that the intuition under discussion, thus explicated and in some ways qualified, makes sense morally. (shrink)