Every day in the animal research laboratory, laboratory animal professionals and IACUCs face large and small decisions about animal welfare. An animal care and use committee receives a protocol application for permission to use dogs to teach a class on surgery and anesthesia for medical students. The professor has done her best to assure that students develop competence using computer simulations of anesthetic responses and good psychomotor skills for suturing and tissue handling using nonliving animal models. Eventually, though, she believes her students develop their best skills by following all of this training with procedures performed on live animals. The committee must consider a host of questions that we won't go into here: choice of anesthetics; qualifications of lab instructors; how the animals will be housed; and many others. Focus for now on the questions of what kind and how many animals the committee will allow. In the interest of reducing animal numbers, should the instructor allow animals to recover from anesthesia so that she may use a smaller number of animals a few times over? Or should she never allow the animals the potential pain of postsurgical recovery and euthanize them while still anesthetized on the surgery table even if that means using more animals? 3 Should she try to switch from dogs to “lower” animals? If so, are rats sufficiently “lower”? What if their smaller size would dictate using a larger number of rats, or made it more difficult to deliver adequate anesthesia and analgesia, or compromised what the students were able to learn from the lab?
How much of an incremental increase in the students' learning justifies inflicting pain or death or both on animals? (Garrett 2009) These are the sorts of questions that animal care and use committees consider at their meetings, not the big question of whether people have any right to use animals in research and teaching. That big question is vitally important, but by the time we are determining cases, it has already been decided in favor of human priority. Yes, we will continue using animals for the foreseeable future; the question is not whether, but how. Can we find guidance from philosophers to help us decide when painless death is preferable to life with some potential pain, to rank species one above another, to rule whether more animals should experience low-level suffering so that a small number do not suffer greatly? Can we figure out which human needs and desires might justify inflicting pain or death on animals? Can we find guidance to make decisions for animals who cannot tell us their preferences and experiences directly? Twin studies and adoption studies It would be reasonable to characterize behavioral genetics research at this time as largely descriptive in nature. Its primary purpose has been to determine what is heritable and to what degree. Over the past two decades the primary research questions has been along the lines of: "Are depression and schizophrenia heritable?," and the answer has been "Yes, about 30% and 80%, respectively." (Garrett 2009) The purpose of multivariate research has been similar. Its task has been to determine why, for example, depressed patients are frequently anxious. The answer has been that depression and anxiety are influenced by some of the same genes. Finding substantial and significant evidence of heritability for the most common mental disorders bodes well for molecular genetic studies attempting to identify susceptibility loci. These methods promise that, once susceptibility genes are identified, before long it will be possible to screen for psychiatric disorders with blood tests and develop pharmacological interventions to mediate gene function. (Garrett 2009) However, this work has been hampered by the diffuse and heterogeneous nature of many psychiatric phenotypes that may reflect competing genetic and environmental influences. The persistent use of these kinds of broad diagnostic categories is inconsistent with the accumulating evidence from family, adoption, and twin studies that have shown many symptoms defining these categories to be differentially familial or heritable. Depending on precisely what is subjected to genetic analysis, quite different answers are found. The typical approach to overcoming this problem is to design more statistically powerful studies that genotype hundreds or thousands of people worldwide, which allows for the testing of more and more closely spaced alleles. This, coupled with high through-put gene sequencing machines, manages any uncertainty by averaging it out and capitalizing on even minimal true genetic effects through aggregation. The research, however, suggests that brute force approaches that rely on bigger and faster studies must also be made better by putting greater consideration into the phenotypes subjected to genotyping analysis. The behavioral genetic literature has shown that many of the ways psychopathology is presently understood and conceptualized could do with some revision so that the phenotype accurately reflects its aetiology. Gene-environment interplay is important. Simply inheriting a liability gene or being exposed to a momentous event often does not lead to mental illness. (Garrett 2009) Genes and the environment influence each other. Two gene-environment interplay effects studied by behavioral geneticists are gene-environment interaction and correlation. Early research had little power to detect these effects, but recent advances in statistical modeling and research design suggest that these effects were previously largely underestimated. There are few studies of these effects currently available, but of those that do exist (e.g., antisocial personality and parental treatment, alcoholism and rural or urban residency), the results are dramatic. Of particular note is that these new models provide the means to explore environment-by-experience interactions, which to date have received little attention. Gender-specific factors are important as well. There is no doubt that some disorders are more prevalent in one gender than another. Sex-limitation analyses have shown that, for many disorders, men and women are influenced by the same genetic and environmental liabilities (e.g., schizophrenia) and only differ in the magnitude of these effects (e.g., anxiety sensitivity and panic). (Garrett 2009) However, there are a number of disorders, such as alcohol abuse, whose variability is attributable to genetic and environmental factors that are largely unique to each gender. Any gender differences in terms of magnitude, genetic effect, or type of effect clearly indicate that gender-specific treatments must not be overlooked.