Don't be afraid of your genes

I've been talking a lot about genes lately (because I'm obsessed) and what I'm finding is that many people are alarmed by genetics. I believe there are two primary reasons for this--one quite valid.

A Vast Social Engineering Project?

This fear of genetics arises, in part, from the belief that we may soon find ourselves enmeshed in a vast social engineering project. Neuroscientists already have the power to tinker with human nature and this power will only increase with time.

It's likely that within the next 10 years, people suffering from post-traumatic stress disorder will have the option of expunging the memories that haunt them. But losing a memory means, in a sense, losing a part of the self. How many will be comfortable re-engineering their minds to this degree?

Even more bewildering is the idea that parents will one day have the ability to "adjust" their children's personalities before they're even born. Shall we extract the selfish gene, a doctor might ask? The ADD gene? The genes that correlate with depression? Depression is a clinical illness that causes a great deal of agony. But it's also associated with a high degree of sensitivity, compassion, and creativity. Will curing the disease blunt these gifts?

The newfound power to re-engineer human nature is both intoxicating and disturbing. What are the side effects of extracting pieces of the human puzzle? Will we lose ourselves in a rush towards perfection?

These are all legitimate concerns. That said, there's no turning back. We're in the throes of a scientific revolution and no amount of wishful thinking will stop it. Genetic advances will force us to redefine what it means to be human.

We can take solace in the fact that we aren't the first generation to wrestle with what it means to be human. Every great scientific paradigm shift, from the Copernican Revolution to Darwinism, "profoundly affected the way in which we view ourselves and our place in the cosmos." (Phantoms in the Brain) Those of us who embrace human idiosyncrasies can only hope that common sense wins out.

The Myth of Genetic Determinism

The second major factor contributing the fear of genetics can be traced back the age-old nature vs. nurture debate. As author Nancy Andreasen says in her excellent book, Brave New Brain:

When people discuss the causes of [human behavior], they frequently fall into a . . . false dichotomy. Are [illnesses] due to genes or environment? . . . The first and most basic problem with this dichotomy is that very few things in human life--normal or abnormal--are due solely to genes, or solely to non-genetic factors.

Many people suffer from the mistaken assumption that their genes determine their destiny. While it's true that genes may predispose you to certain conditions, like heart disease, manic depression, or breast cancer, possessing a genetic marker doesn't seal your fate.

Genes are a two way street. Your actions influence their behavior. If you are genetically predisposed to alcoholism, this doesn't mean that you will inevitably become an alcoholic. If you're prone to alcoholism and you guzzle a pint of vodka everyday--well, yeah, chances are, you'll become an addict. If, however, you drink in moderation, stay aware, and treat your body with respect, you can easily avoid the disease.

A healthy-living individual with a predisposition to alcoholism is far less likely to fall prey to addiction, than a chronic alcohol abuser with no genetic proclivity. By over-imbibing on a regular basis, the "normal" drinker will change his brain chemistry. He will, in fact, alter his genes. The satisfaction centers of his brain will become dependent on the substance. When he stops using, his levels of CREB (Got CREB?) will dip; he'll become extremely anxious; and he'll be inclined to drink again to produce the chemical cocktail necessary for serenity.

A good example of just how "plastic" genes are is myopia, or near-sightedness. The prevalence of myopia in our society suggests that it's genetically predetermined. It's not. People genetically prone to myopia only develop the disorder if they engage in a particular behavior: reading. Recent studies have shown that "genes cause short sight only in those who learn to read. In societies where few people read, myopia will correlate more closely with reading than with 'myopia genes.'" (Genes So Liberating)

Obviously, few of us are so put out by near-sightedness that we'd opt for illiteracy. But this example illustrates my point: possessing certain genes doesn't rob us of free will.

Instead of fearing your genes, get to know them. Take note of diseases that run in your family and make decisions that support your health. And keep in mind that, as neuroscientists plumb the depths of the genetic code, we become increasingly likely to stumble on cures for diseases. Knowing that genes respond to their environment "frees us from genetic determinism," Dr. Andreasen says, and "It offers us hope that we will some day learn ways to modify the genetic instructions that lead to diseases."

Tags
Categories

More like this

Futurepundit has an interesting post based on a new paper about so-called junk DNA. Only 2% or so of the human genome actually encodes protein sequences. The rest is a grab-bag of broken genes and virus-like sequences called mobile elements that hijack the cell's DNA copying-machinery from time to…
David Dobbs has a wonderful article in the most recent Times Magazine on Williams syndrome, a development disorder that results in a bizarre mixture of cognitive strengths and deficits: Williams syndrome rises from a genetic accident during meiosis, when DNA's double helix is divided into two…
tags: bipolar disorder, manic-depressive illness, mental health, molecular biology Bipolar disorder depends upon small, combined effects from variations in many different brain genes, none of which is powerful enough by itself to cause the disease, according to a new genome-wide study. Despite this…
Purcell et al. (2009). Common polygenic variation contributes to risk of schizophrenia and bipolar disorder Nature DOI: 10.1038/nature08185 Neil Walker has been doing a spectacular job of serving up useful information in the comments recently, so I asked him to write the first ever guest post on…