Behavioral Genetics - The Clash of Culture and Biology - R. Carson, M. Rothstein (1999) WW

226 Pages·1999·1.87 MB·English

Behavioral Genetics

Behavioral Genetics

The Clash of Culture and Biology

Edited by

Ronald A. Carson

Harris L. Kempner Distinguished Professor

in the Humanities in Medicine

Director, Institute for the Medical Humanities

University of Texas Medical Branch at Galveston

Galveston, Texas

and Mark A. Rothstein

Hugh Roy and Lillie Cranz Cullen

Distinguished Professor of Law

Director, Health Law and Policy Institute

University of Houston

Houston, Texas

The Johns Hopkins University Press

Baltimore and London

© 1999 The Johns Hopkins University Press
All rights reserved. Published 1999
Printed in the United States of America on acid-free paper
9 8 7 6 5 4 3 2 1

The Johns Hopkins University Press
2715 North Charles Street
Baltimore, Maryland 21218-4363
www.press.jhu.edu

Library of Congress Cataloging-in-Publication Data
will be found at the end of this book.
A catalog record for this book is available from the British Library.

ISBN 0-8018-6069-5

Contents

Foreword, by Floyd E. Bloom
vii
Preface and Acknowledgments
ix
List of Contributors
xv

1.
Amazing Grace: Sources of Phenotype Variation
in Genetic Boosterism
Allan J.Tobin
1

2.
In the Mainstream: Research in Behavioral Genetics
David C. Rowe and Kristen C. Jacobson
12

3.
Identifying the Molecular Genetic Basis
of Behavioral Traits
Stephanie L. Sherman and Irwin D.Waldman
35

4.
Complexity and Research Strategies
in Behavioral Genetics
Kenneth F. Schaffner
61

5.
Behavioral Genetic Determinism:
Its Effects on Culture and Law
Mark A. Rothstein
89

6.
Predicting and Punishing Antisocial Acts: How the
Criminal Justice System Might Use Behavioral Genetics
Lori B.Andrews
116

7.
Behavioral Genetics and Dismantling the Welfare State
Dorothy Nelkin
156

8.
The Social Consequences of Genetic Disclosure
Troy Duster
172

9.
The Fate of the Responsible Self in a Genetic Age
Ronald A. Carson
189

Index
201

As a medically trained neuroscientist, my lifelong approach to
diseases of the brain and behavior has been to search deeper and deeper into
the causal mechanisms and points of biological vulnerability. Medical scien-
tists frequently employ vertical thinking, which in terms of the brain and its
disorders is a much richer expression than the “reductionist” appellation fre-
quently used to cast aspersions of simple-mindedness onto biologists who
rarely bother with psychosocial causes of illness. By thinking vertically, I am
not satisfied just with finding genes that may mark vulnerability or resistance
to a disease. Rather, I want to understand how the products of that gene, ex-
pressed selectively or ubiquitously, or somewhere in between, can influence
neurons or glia; disregulate circuit formation or function; influence integrated
functional systems; and change the way an individual interacts with, perceives,
or anticipates the environment. Studies in which I have been a participant for
more than fifteen years continue to strengthen the view that the brain relies on
more genes to carry out its functions than any other organ in the body, and
that more than half of the mammalian genome is of use to the brain. The Hu-
man Genome Project has already identified more than 40,000 bits of brain
genes and I am thrilled at the information we will have on neuronal pheno-
types and their functional variations once those initial discoveries have been
characterized as to sites and times of expression.
In one of my longest-running fields of endeavor, namely, vulnerability to al-
coholism, I have been impressed with the way family histories support the ten-
dency for vulnerability to alcoholism to run in families, often with devastating
influence, in a male-to-male transmission pattern. Being predisposed to accept
the validity of that human pattern, I am further predisposed to accept the re-
sults of studies on rats bred to express greater and greater desire to drink alco-
hol and to show by their behavior that they will work to gain access to the al-
cohol. The data derived from the studies of these alcohol-preferring rodents
also show comparable responses to drugs that help reduce alcohol ingestion
and reduce recidivism in humans. Invasive studies of the alcoholic rats have re-
vealed certain consistent alterations in brain neurochemistry and cellular func-
tion. However, there is still much to be learned before scientists will have a list
of discrete gene expressions that will allow them to compare the alcohol-pre-

Foreword

ferring animals and the alcohol-ignoring animals, let alone understand which
combinations of changes may be the cause of the apparent simulation of the
human alcoholic’s condition.
Does this indicate that psychosocial factors and social culture have no bear-
ing on the quest for understanding? No, not at all. When alcohol-preferring
rats are placed in an environment in which they previously worked to obtain
their alcoholic beverage, they begin to show the same neurochemical changes
they showed when they were actively working to obtain alcohol. If these ani-
mals are never given a chance to drink, they clearly have no problems main-
taining their simple existence and reproducing in laboratory settings.
Do I think there is only one gene “responsible” for alcoholism, or any other
complex behavioral disease of emotion, cognition, or social interaction? Cer-
tainly not. I simply do not yet have a glimmer of the ways in which specific
gene abnormalities of the sorts that are consistently observed in Huntington
disease and that are occasionally observed in Alzheimer and Parkinson diseases
can lead to the late-life devastations that characterize these untreatable pa-
thologies. Those pathways need to be determined before we can have any
prospects for understanding the still more variable biological bases by which
some families show greatly increased incidences of other psychopathologies,
and in which the consistent nonreproducibility of specific gene associations
across such families suggests that there may be numerous routes to increased
biological vulnerability.
Clearly, at present we have an incomplete genetic inventory of the brain and
hence of the consequences for brain assembly, homeostatic adaptation, ability
and desire to learn, and whatever goes into resilience to internal and external
stressors. Nevertheless, this ignorance is slowly being reduced, and the only
clash I see is with those who would take the view that the rich biology of the
brain is irrelevant to the causes of mental diseases, or to their cure or ultimate
prevention. In my view, this strategy does not have the remotest chance of suc-
cess.Yet as scholars, we are required to keep an open mind, to be willing to hear
and assess a variety of data as well as concepts and hypotheses, and then, if suf-
ficiently challenged, to find ways to test those hypotheses. As this book amply
demonstrates, there are many contrasting views and much data to be gathered
if contrasting views of the causes of behavioral disorders are to be unified.

Floyd E. Bloom, M.D.
Department of Neuropharmacology
The Scripps Research Institute
La Jolla, California

viii
Foreword

Modern science is a product of Western culture. Its practitioners
and laypersons alike take for granted culture-specific conceptions of self and
society, freedom, responsibility, and human flourishing. Current developments
in genetics are prompting a reevaluation of those ideas and a reconsideration
of what constitutes responsible use of new knowledge.
The Human Genome Project is proceeding on schedule, with experts pre-
dicting that the entire genome sequence will be completed no later than 2005.
Much of the scientific attention has already shifted away from single-gene disor-
ders,such as cystic fibrosis,to complex disorders,such as various cancers.Lurk-
ing only slightly away from the glare of attention, however, like an uninvited
guest sitting in a corner, are thorny issues surrounding behavioral genetics.
Genetic diseases have understandably garnered most of the attention so far.
The promise that pernicious and intractable human diseases could be identi-
fied in advance and treated, or even prevented, has supplied the moral power
to drive the engine of the Human Genome Project. However, important ethi-
cal, legal, and social issues are being raised in determining how our health care
system will respond to new genetic discoveries. The issues include access to
technology, genetic counseling, reproductive freedom, informed consent, and
the role of genetics in public health. The use of genetic information for non-
medical purposes, such as insurance, employment, domestic relations, and fo-
rensics, has spurred a reexamination of notions of privacy and confidentiality.
Claims of genetic factors in behavior have been slower to develop. Indeed,
genetic research on mental illness, for example, often has been characterized by
false premises, unreplicated claims, and retracted papers. There are many rea-
sons for this, including the difficulty of establishing diagnostic criteria, com-
plex modes of inheritance, multiple gene interactions, difficulty in measuring
end points, problems of methodology, and the uncertain effects of environ-
ment. These research problems are intensified for nonpathological behavioral
factors. Nevertheless, assertions of a genetic link to thrill seeking, aggression,
nurturing, aging, the development of language and social skills in women,
“handedness,” and food preferences all have been announced recently. Sexual
orientation, alcoholism and other addictive behavior, and intelligence have
surfaced to varying degrees as well. Our individual and collective responses to

Preface and Acknowledgments