The tug-o-war

Your DNA was sent to a lab for analysis and these results came out:

The good news: Brilliance runs in your family.

The bad news: It runs in a zigzag pattern and guess who it missed this time?

Hmm, now what? Could you change your genes or send out a complaint cum request form for replacement genes? Could you zig genes to ensure that this brilliance which runs in your clan zags you? The DNA finding above was a joke that I came across. I am not sure if there are even genes for brilliance. Since the sequencing of the human genome about a decade ago, science has been coming up with a suspect gene for a certain talent, illness or behavior. I have to say that if there were genes for dexterity, they sure zigzagged in my family too, completely missing me. But there is a recent study that showed that experience could tweak a gene and maybe, there is hope for genes that you may be stuck with.

For a quick lesson on genes, let us just say that by just being alive, you automatically gain entry to the tug-o-war event between your nature (genes) and nurture (experiences). Genes do not have the ultimate say of how you will turn out; they just give you a tendency for certain illnesses, certain behaviors or talents. The environment — the people, places, things and events which make up your experience — is the other end of the tug-o-war game.

In the journal Nature Neuroscience, also reported in BBC last Nov. 11, a team of researchers led by Christopher Murgatroyd from the Max Planck Institute of Psychiatry in Munich, Germany, revealed their findings of not just how early stress could change a gene in mice but also how this actually happens.

The experiment separated newborn mice for three hours for 10 days from their mothers and tried to see how this kind of early stress could affect the young mice in the long term. They observed that mice who were stressed this way found it much more difficult to cope with other challenges later in life and these same mice had poorer memories compared to the ones who were not made to suffer early stress. The study even went further to peer into what happens to these mice and they saw that under stress, these mice produce high levels of stress hormones. These stress hormones in turn were able to tinker with the gene responsible for producing another hormone called vasopressin, producing it in abnormally high levels. Too much vasopressin has been associated with problems that have to do with memory and behavior. They double-checked their findings by blocking the effects of vasopressin in the affected mice and the mice became normal. From these results, scientists want to do further studies to see how this could apply to humans. This could be very important in strengthening support and encouragement for early life experiences so that kids would not have crippled coping mechanisms later on.  

Indeed, genes do affect your tendencies for certain behaviors. A separate but related article in the Atlantic Monthly this month entitled “The Science of Success” by David Dobbs gave a good overview of research on certain genes that “make people more vulnerable to certain mood, psychiatric, or personality disorders.” He mentioned that in the past 15 years of research, a dozen-odd gene variants have been identified which “increase a person’s susceptibility to depression, anxiety, attention-deficit hyperactivity disorder, heightened risk-taking, and antisocial, sociopathic, or violent behaviors, and other problems.” The operative phrase is “increased susceptibility” which means that it is not an absolute effect that you will have these problems if you have any or a combination of those genes.

While the mice experiment I earlier mentioned demonstrates how a negative experience could change your genes, I also came across some studies that show how positive experiences can change a “negative” gene. I learned about nurture’s power in a video included in the Atlantic article. It was an interview with a scientist named Stephen Suomi who has been studying monkeys. He observed that those who were “trouble” monkeys in terms of their aggression and incapacity to learn were the ones who have the short version of the serotonin transporter gene. Serotonin is a hormone responsible for mood and memory, among other things. The monkeys with the long version of the gene were shall we say, “balanced” monkeys. But that is not what was fascinating. What really demonstrated the power of nurture was when those with the shorter gene version were nurtured by their mothers, they did not exhibit troublesome beha­vior despite their shorter genes.

When you go to your holiday reunions, take a good look at your relatives, even the annoying ones (especially the annoying ones). What genes may have hit or missed you as they were passed on through time? But don’t stop there, also notice how the individual lives of your family members turned out differently despite sharing many genes among yourselves. Family reunions are good settings to affirm that neither genes nor experience alone define who we are. It indeed is a tug-o-war, every day, in every life.

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