The Heritability of Human Behavior: Results of Aggregating Meta-Analyses

The heritability of human behavior can be estimated through studies comparing MZ and DZ twins and through adoption studies. Meta-analyses have estimated the heritability of intelligence, mental chronometric performance, language ability, anxiety disorders, major depression, antisocial behavior, problem drinking, and smoking. This article presents the aggregation and analysis of these meta-analyses, which included a total of over four hundred samples. The results of the aggregation suggest that about 41% of human behavior is genetically influenced, a percentage that may have evolutionary value. Some significant moderators were found in more than one meta-analysis, including greater heritability (a) in more disordered levels of a behavior for performance on a language-ability test, antisocial behavior, and smoking and (b) in females for antisocial behavior and smoking initiation. The moderator findings raise questions about what might explain the identified differences in level of heritability.     

The Importance of Program Evaluation: How Can it be Applied to Diverse Genetics Education Settings?

The role of a genetic counselor often entails providing education to patient, community and/or health professional groups. While counseling supervision assists genetic counselors to be reflective about their clinical work and to enhance clinical skills, evaluation is a rather analogous process in the provision of education. Program evaluation of education activities can be applied to provide information about the needs of the target group (needs assessment), the delivery of the program (process evaluation) as well as determining the extent to which the education activity has met its intended aims (summative evaluation). Evaluation assists the educator to assess the impact of their program and provides an evidence base about genetics education. Although program evaluation can be a complex activity, the tools are ones that can be used by individuals to evaluate single or simple education activities. The components of evaluation are discussed with reference to genetic counseling practice and three very different examples of actual evaluations are provided to illustrate the diversity of evaluation strategy and programs to which it can be applied.     

GENETIC AND REPRODUCTIVE TECHNOLOGIES IN THE LIGHT OF RELIGIOUS DIALOGUE

Since the gene splicing debates of the 1980s, the public has been exposed to an ongoing sequence of genetic and reproductive technologies. Many issue areas have outcomes that lose track of people's inner values or engender opposing religious viewpoints defying final resolution. This essay relocates the discussion of what is an acceptable application from the individual to the societal level, examining technologies that stand to address large numbers of people and thus call for policy resolution, rather than individual fiat, in their application. A major source of guidance is the “Genetic Frontiers” series of professional dialogues and conferences held by the National Conference for Community and Justice from 2002 to 2004. Genetic testing, human gene therapy, genetic engineering of plants and animals, and stem cell technology are examined. While differences in perspective on the beginning of life persist, a stepwise approach to the examination of genetic testing reveals areas of general agreement. Stewardship of life, human co‐creativity with the divine, and social justice help define the bounds of application of genetic engineering and therapy; compassionate care plays a major role in establishing stem cell policy. Active, sustained dialogue is a useful resource for enabling sharing of religious values and crystallization of policies.     

Three Laws of Behavior Genetics and What They Mean

Behavior genetics has demonstrated that genetic variance is an important component of variation for all behavioral outcomes, but variation among families is not. These results have led some critics of behavior genetics to conclude that heritability is so ubiquitous as to have few consequences for scientific understanding of development, while some behavior genetic partisans have concluded that family environment is not an important cause of developmental outcomes. Both views are incorrect. Genotype is in fact a more systematic source of variability than environment, but for reasons that are methodological rather than substantive. Development is fundamentally nonlinear, interactive, and difficult to control experimentally. Twin studies offer a useful methodological shortcut, but do not show that genes are more fundamental than environments.     

Molecular (moment-to-moment) and molar (aggregate) analyses of behavior

Ten meanings or usages of the terms molecular and molar analyses are based on (1) numbers of responses, (2) durations of activities, (3) levels, (4) scales, (5) contiguity versus correlation, (6) behavioral standards, (7) function with or without structure, (8) local versus global phenomena, and (9) control by shaping of sequential moment-to-moment behavior. These usages reveal divisive viewpoints along with ambiguities in the Law of Effect, the definition of an operant, response strength, response probability, random behavior, time allocation, shaping, controlled versus uncontrolled operants, and roles for ordinary language. Usage 10 is less divisive and combines, and in that sense unifies, molecular behavior, defined as shaped moment-to-moment sequential behaving, and molar, defined as averages of aggregates of those shaped responses. It combines shaping, that establishes and changes operant behaviors, and strengthening that changes the amounts of those shaped behaviors. I conclude that general behavioral theory will combine strengthening with such methods as parametric, hybrid, or nonparametric shaping, and will use computational methods to simulate moment-to-moment behavior streams from which any aggregates of theoretical interest may be computed. Such a synthesis may not require different levels, scales, or new scientific paradigms.     

Scaling Up the Self,Scaling Down the World: Self-objectification and the Politics of Carbon Offsets and Personalised Genomics

Two global initiatives, the Genographic Project and the Carbon Lottery, share an ambition to make abstract, global processes—human evolution and climate change—comprehensible and engaging to non-specialists. Despite their differences, they both do so by means of self-objectifications that scale up the selves of participants and scale down complex, spatio-temporal models of human–world relations. The author’s auto-ethnographic experiences in both initiatives illustrate how carbon calculators and personalised genomics involve a pragmatics of scale that evaluates and compares users on the basis of their relative expression of, or deviation from, a standard. Furthermore, this is not based on actual resources that participants do or do not possess, but on forms of capitalist exchange that underwrite carbon trading and population genomics, as experts and corporations make intellectual property derived from purportedly rare DNA and sustainable practices, which are typically indigenous and non-western. In fact, the global inequalities that make possible transactions in carbon offsets and genetic ancestry are obscured from view. As a result, though initiatives like the Genographic Project and Carbon Lottery may provide comprehensible self-objectifications, they potentially make the world more unequal in the process.     

Toward the Unification of Molecular and Molar Analyses

Three categories of behavior analysis may be called molecular, molar, and unified. Molecular analyses focus on how manual shaping segments moment-to-moment behaving into new, unified, hierarchically organized patterns. Manual shaping is largely atheoretical, qualitative, and practical. Molar analyses aggregate behaviors and then compute a numerical average for the aggregate. Typical molar analyses involve average rate of, or average time allocated to, the aggregated behaviors. Some molar analyses have no known relation to any behavior stream. Molar analyses are usually quantitative and often theoretical. Unified analyses combine automated shaping of moment-to-moment behaving and molar aggregates of the shaped patterns. Unified controlling relations suggest that molar controlling relations like matching confound shaping and strengthening effects of reinforcement. If a molecular analysis is about how reinforcement organizes individual behavior moment by moment, and a molar analysis is about how reinforcement encourages more or less of an activity aggregated over time, then a unified analysis handles both kinds of analyses. Only theories engendered by computer simulation appear to be able to unify all three categories of behavior analysis.     

Tensile deformation mechanisms of the hierarchical structure consisting of both twin-free grains and nanotwinned grains

A series of large-scale molecular dynamics simulations have been performed to investigate the tensile properties and atomistic deformation mechanisms for the nanostructured Cu with three typical microstructures: the hierarchical structure consisting of both twin-free grains (d?=?70?nm) and grains with bundles of smaller nanotwins (d?=?70?nm, λ?=?10?nm), the fully nanograined structure and the fully nanotwinned structure. The average flow stress of the hierarchically structure is found to be higher than that calculated by rule of mixture. As compared with that of fully nanograined structure, the strength for the twin-free grains in the hierarchical structure is promoted and gives extra hardening due to the increased dislocation density and dislocation behaviours. It is also found that the nanotwin bundles are more deformable than the twin-free grains in the hierarchical structure according to the deviatoric strain invariant contour. This indicates that the fully nanograined structure cannot only be strengthened to a higher level, but also obtain better ductility by embedded with stronger bundles of smaller nanotwins. Thus, a superior strength–ductility synergy could be obtained in this kind of hierarchical structures, and this novel strategy has also been implemented in bulk austenitic steels or copper by recent experiments.