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Recent developments in molecular biology have caused even the staunchest disciplinary proponents of the “nurture” side of the nature-nurture debate to acknowledge the potential role of genetics in understanding human behavior. Sociology – my own discipline and long a champion of “environmental” explanations of human behavior – is coming to recognize the value of adding genetic factors to its arsenal of explanatory variables. The eminent medical sociologist Pescosolido (2006), in her Reeder Award Lecture presented to the Medical Sociology Section of the American Sociological Association, points to this emerging awareness:

Signaling “symbolic inheritances” (e.g., beliefs surrounding gender, health, religion) and “behavioral inheritances” (i.e., embodied “scripts” that mold everyday routines affecting health and illness behaviors) calls for research to suggest a “new appreciation of the coactivity of nature and nurture.” (p. 190)

And sociologists have just seen the publication of a special supplement to the American Journal of Sociology – one of the discipline’s flagship journals – devoted to the respective contributions of genetics and social structure (Bearman, Martin, &c Shostak, 2008).

That the biological and social – as well as behavioral – dimensions of aging intersect and have implications for one another has, of course, long been a central tenet of gerontology. Indeed, one of the seven areas identified by the National Institute on Aging’s (2009) Division of Behavioral and Social Research as a major focus of emphasis in its research portfolio is the topic of “genetics, behavior, and the social environment” (para. 3).

In view of the dramatically increasing prominence of genetics – along with a host of attendant scientific, policy, and ethical issues and challenges Read, Green, and Smyer’s Aging, Biotechnology, and the Future is a timely and welcome contribution to the literature. Based on the proceedings of a March 2005 conference at Boston College, the book aims to probe the implications of two intersecting revolutions: population aging and biotechnology. The contributors come from a broad array of disciplines: medicine, law, biology, psychology, gerontology, nursing, philosophy, ethics, and religion. Many of the authors are well known to gerontologists (e.g., Gatz, Perls, Poon, Miles); others will be less familiar, but collectively they represent an eclectic and distinguished group.

After a useful overview and a brief introductory section, subsequent parts of the book deal with immortality (e.g., cloning, potential applications of stem cell technology, anti-aging technologies), research on centenarians, issues in the use and application of genetic testing, and ethical and social issues arising from the biotechnology revolution. Readers will find most of the individual chapters to be of interest, and the major themes recurring throughout the volume point to scientific, policy, and ethical questions that warrant our careful consideration.

For example, a central thread running through several chapters is the issue of justice or how scarce technological resources will be allocated within and between societies. Both Sprott and Guerra see access to the benefits of biotechnology as being among the principal challenges flowing from the biotechnology revolution. Questions about cross-national inequities in access to stem cell technology and potential extensions in life expectancy are central to Lebacqz’s chapter. And Cahill and Moses, in their chapter on “Aging, Genetics, and Social Justice,” develop these issues in the greatest depth. Among the significant questions they raise are the following: Are resources allocated to the biotechnology revolution being diverted from other, more pressing needs? To whom will the fruits of the biotechnology revolution be available? Will cross-national biotechnological divides lead to even greater gaps in life expectancy than is now the case?

Expressed in various ways in several of the chapters is a reminder that the enormous promise of the biotechnology revolution must not cause us to lose sight of the role played by environmental factors. Perls, Poon, and Scott-Jones, in their respective contributions, explore factors associated with living more than 100 years. A consistent theme in their work is that both genes and environment contribute to longevity but in complex ways and as yet in quantitatively indeterminate amounts. In reviewing what we know about the respective roles of genes and environment in the development of Alzheimer’s disease, Gatz and Brommelhoff review the role of environmental factors that have been posited as contributing to Alzheimer’s disease but caution that we are a long way from knowing how they operate and from an understanding of how environmental and genetic factors might interact.

A particularly interesting set of conclusions is to be found in the chapters examining the implications of genetic testing based on results from the Risk Evaluation and Education for Alzheimer’s Disease (REVEAL) study, an exemplary investigation that brings rigorous design and a blend of quantitative and qualitative approaches to questions of great practical significance. It is well accepted that the APOE gene, located on chromosome 19, has probabilistic implications for one’s chances of developing Alzheimer’s disease. This has occasioned debate about the wisdom of allowing individuals to learn which of the APOE alleles they carry, their APOE “status.” As Pamela Grace notes in her chapter on “Genetics, Aging, and Primary Care: Ethical Implications for Clinicians,” the principles of nonmaleficence and beneficence might be used to argue that individuals need to be protected from the possible emotional toll of learning they have a heightened probability of Alzheimer’s disease, especially given the absence of a cure and only very limited treatment effectiveness. The principle of autonomy, in contrast, makes the claim that people have a right to acquire the knowledge about themselves that will enable them to make informed choices. Largely missing from this debate, however, has been rigorous evidence on the question of whether learning one’s APOE genetic status actually results in threats to psychological and physical well-being. What the REVEAL study does is to compare outcomes among participants receiving genetic counseling and risk assessment based on gender, family history of Alzheimer’s disease, and APOE genotype and participants receiving counseling and risk assessment based on gender and family history, but not APOE genotype. The results demonstrate that those receiving APOE genotype disclosure did not experience the types of adverse outcomes that have long been used to justify making access to APOE testing difficult to come by.

Although the REVEAL study shows that “genotype information can be disclosed safely and meaningfully if appropriate education and genetic counseling are provided” (p. 140), more recent work takes this finding a step further by suggesting that even the disclosure of deterministic genetic information about early-onset familial Alzheimer’s disease does not result in clinically significant distress (Cassidy et al., 2008). With the growing interest in genetic testing – what Pinker (2009) refers to as “consumer genetics” – it is essential that discussions of the effects of acquiring genetic information move from the realm of speculation to the kind of rigorous evidence provided by REVEAL and related studies.

As with almost any edited collection, there is some unevenness in depth and quality among the chapters. Readers also will find variability in the degree to which explicit attention is paid to the implications for aging of developments in biotechnology. Nevertheless, Aging, Biotechnology, and the Future is a thought-provoking starting point for anyone interested in the varied and reciprocal implications of population aging and developments in biotechnology.

Stephen J Cutler.  (2009). AGING AND GENETICS: THE FUTURE IS HERE. Review of medium_being_reviewed title_of_work_reviewed_in_italics. The Gerontologist, 49(2), 283-285.  Retrieved June 20, 2009, from Research Library database.