In order for genes and environment to interact in this way, they
need to be in constant conversation, back and forth. Since parents
usually raise the children to whom they have passed on their genes,
that's rarely a problem: they are likely to share and perhaps appreciate
the qualities of their offspring. And the environment they provide their
children with may further support their natural abilities: highly
literate parents might give birth to an equally verbal child, then raise
her in a house full of books. Developmental psychologists call this
fortunate match "goodness of fit." But problems may arise if nurture and
nature aren't on speaking terms -- if a child's environment doesn't permit
or encourage expression of his natural tendencies. That may happen when
children's abilities don't match their parents' expectations; when their
genetically-influenced temperament clashes with that of their parents; or
when their environment offers them few opportunities to express
themselves constructively, as is often the case with children who grow up
in severe poverty. Research has shown that a poor person-to-environment
match can lead to decreased motivation, diminished mental health, and
rebellious or antisocial behavior.
The dialogue between genes and environment becomes more complicated
when a sibling adds another voice. Although siblings share an average of
50 percent of their genes, the half that is different -- and the
kaleidoscopic ways that genes can combine -- leads their genotypes to ask
different questions and get different answers from what would seem to be
the same environment. In fact, siblings create individual environments of
their own by seeking out different experiences and by evoking different
responses from parents, friends, and others. Like the proverbial blind
men touching the leg, the trunk, or the tail of an elephant, they "see"
different parts of the same animal. "Our studies show that parents do
indeed treat their children differently, but that they are in large
measure responding to differences that are already there," says Robert
Plomin. "Family environment does have an effect on personality
development, but not in the way we've always thought. It's the
experiences that siblings don't share that matter, not the ones they
do."
KIDS IN CHARGE?
One intriguing implication of behavioral genetic research is that
children are in many ways driving their own development, through the
choices they make, the reactions they elicit, even the friends they pick
(see "The Power of Peers," below). But parents are crucial collaborators
in that process, and that means that their role in shaping their children
may actually be larger than it first appears. How a parent responds to a
child's genetically-influenced characteristics may make all the
difference in how those traits are expressed, says David Reiss. In his
formulation, the parent-child relationship acts as a sort of translator
of genetic influence: the genotype provides the basic plot, but parenting
gives it tone and inflection, accent and emphasis. He calls this
conception of gene-environment correlation "the relationship code," and
says that it returns to parents some of the influence his study would
seem to give to genes. "Our data actually give the role of parents a real
boost -- but it's saying that the story doesn't necessarily start with the
parent," says Reiss. "It starts with the kid, and then the parent picks
up on it."
To Reiss, parents' role as interpreters of the language of heredity
holds out an exciting possibility. "If you could intervene with parents
and get them to respond differently to troublesome behavior, you might be
able to offset much of the genetic influence" on those traits, he says.
In other words, if genes become behavior by way of the environment, then
changing the environment might change the expression of the genes.
Although such intervention studies are years away from fruition,
small-scale research and clinical experience are pointing the way toward
working with children's hereditary strengths and weaknesses. Stanley
Greenspan, M.D., a pediatric psychiatrist at George Washington Medical
School and author of The Growth of the Mind, is actively applying the
discoveries of genetics to parenting. "Genes do create certain general
tendencies, but parents can work with these by tailoring their actions to
the nervous system of the child," says Greenspan. He believes that the
responses children "naturally" elicit may not be in their best
interests -- but that parents can consciously and deliberately give them
the ones that are. "You have to pay attention to what you're doing
intuitively, and make sure that is what the kids really need," he
says.
Tags:
adolescent development,
child development,
collaborators,
conclusions,
david reiss,
delinquent behavior,
environment,
genes,
george washington university,
healthy kids,
initial results,
paradigm,
parent,
peers,
tendencies
