Saturday, April 24, 2004
NATURE & NURTURE
Genes' impact can be alteredGenetic information can lead to helpful interventions for those needing
assistance to mitigate problems
BY GARY MARCUS
Gary Marcus, a professor of psychology at New York University, is the author
of "The Birth of the Mind: How a Tiny Number of Genes Creates the Complexity
of Human Thought." This is from the Los Angeles NewsDay
April 22, 2004
The human brain has been described as everything from the "last frontier"
and "biology's greatest challenge" to "the most elaborate structure in the
known universe" and Woody Allen's "second-favorite organ."
With rapid advances in genetics, neuroscience and psychology, we will soon
have a radically improved understanding of the contribution of genes to the
developing brain.
Used wisely, that knowledge could lead to an entirely new approach to
social intervention. But doing so will require overcoming common
misconceptions about how genes operate.
Genes are widely seen as either blueprints or deterministic dictators.
Neither view is correct. A single organism's collection of genes - its
genome - can lead to many different outcomes, depending on the surrounding
environment.
The African butterfly bicyclus anyana, for example, can take on two
different forms - colorful in the rainy season and dull brown in the dry
season - depending on how its genes are switched on and off.
The consequences of the responsiveness of genes to the environment may be
even more profound in a human. A butterfly's coloration pattern may only be
skin deep, but the switching of human genes in response to the environment
may profoundly shape our personalities.
Contrary to our usual belief that genes force us toward one possibility
rather than another, biology is revealing a different picture in which genes
arm us with ways of responding to different environments.
One example: A recent study - still preliminary, but breathtaking in what it
might mean - suggests that people who bear a particular version of an enzyme
known as MAO-A are predisposed to violence, but only if raised in abusive
environments.
This particular version of MAO-A is better thought of not as a gene "for
violence" but as a gene that leads its bearers to different kinds of
strategies, depending on their environments.
Given that genes themselves are responsive to the environment, and
responsive in different ways in different people, a bold new possibility
suggests itself, akin to an idea that has taken hold in medicine under the
name of pharmacogenetics.
The idea behind pharmacogenetics is that different people respond
differently to different drugs depending on their own individual chemistry.
Depending on your genes, one version of a drug may be more effective,
another less so.
Doctors are already beginning to incorporate this sort of information into
the prescription of certain powerful drugs, and they will do so more and
more as our understanding of genes grows.
Just as pharmacogenetics tailors medical intervention to individual genetic
profiles, a new field of "social-intervention genetics" could be tailored to
individual genetic profiles.
For example, other things being equal, society would get the most for its
social intervention buck by specifically offering certain social welfare
programs to those with the predisposing form of the MAO-A gene.
Genetic information should never be used to dictate who gets to (or, worse,
doesn't get to) reproduce; nor should society mandatorily impose
intervention where it is not wanted. But by helping to make social
interventions available to those who need them most, our growing
understanding of nature could help us get the most out of nurture.
Copyright © 2004, Newsday, Inc.
Genes' impact can be alteredGenetic information can lead to helpful interventions for those needing
assistance to mitigate problems
BY GARY MARCUS
Gary Marcus, a professor of psychology at New York University, is the author
of "The Birth of the Mind: How a Tiny Number of Genes Creates the Complexity
of Human Thought." This is from the Los Angeles NewsDay
April 22, 2004
The human brain has been described as everything from the "last frontier"
and "biology's greatest challenge" to "the most elaborate structure in the
known universe" and Woody Allen's "second-favorite organ."
With rapid advances in genetics, neuroscience and psychology, we will soon
have a radically improved understanding of the contribution of genes to the
developing brain.
Used wisely, that knowledge could lead to an entirely new approach to
social intervention. But doing so will require overcoming common
misconceptions about how genes operate.
Genes are widely seen as either blueprints or deterministic dictators.
Neither view is correct. A single organism's collection of genes - its
genome - can lead to many different outcomes, depending on the surrounding
environment.
The African butterfly bicyclus anyana, for example, can take on two
different forms - colorful in the rainy season and dull brown in the dry
season - depending on how its genes are switched on and off.
The consequences of the responsiveness of genes to the environment may be
even more profound in a human. A butterfly's coloration pattern may only be
skin deep, but the switching of human genes in response to the environment
may profoundly shape our personalities.
Contrary to our usual belief that genes force us toward one possibility
rather than another, biology is revealing a different picture in which genes
arm us with ways of responding to different environments.
One example: A recent study - still preliminary, but breathtaking in what it
might mean - suggests that people who bear a particular version of an enzyme
known as MAO-A are predisposed to violence, but only if raised in abusive
environments.
This particular version of MAO-A is better thought of not as a gene "for
violence" but as a gene that leads its bearers to different kinds of
strategies, depending on their environments.
Given that genes themselves are responsive to the environment, and
responsive in different ways in different people, a bold new possibility
suggests itself, akin to an idea that has taken hold in medicine under the
name of pharmacogenetics.
The idea behind pharmacogenetics is that different people respond
differently to different drugs depending on their own individual chemistry.
Depending on your genes, one version of a drug may be more effective,
another less so.
Doctors are already beginning to incorporate this sort of information into
the prescription of certain powerful drugs, and they will do so more and
more as our understanding of genes grows.
Just as pharmacogenetics tailors medical intervention to individual genetic
profiles, a new field of "social-intervention genetics" could be tailored to
individual genetic profiles.
For example, other things being equal, society would get the most for its
social intervention buck by specifically offering certain social welfare
programs to those with the predisposing form of the MAO-A gene.
Genetic information should never be used to dictate who gets to (or, worse,
doesn't get to) reproduce; nor should society mandatorily impose
intervention where it is not wanted. But by helping to make social
interventions available to those who need them most, our growing
understanding of nature could help us get the most out of nurture.
Copyright © 2004, Newsday, Inc.
// posted by Linda Weissinger Lupowitz @ 4:02 PM 
