Genetics - Does It Really Matter?

A recent Wall Street Journal article (Nov. 4, 2005, B1faulty human body.
"Linking DNA Profiles to Diseases May Not Lead toIn other words, the body can overcome 'bad' DNA,
Prevention" by Sharon Begley) made a startling point:just like it overcomes the common cold.
DNA may not be the cause of disease. We've allWhat's not often talked about is that scientists have
been told that your DNA is the "cause" of certainnever really gotten to the bottom of DNA. They've
diseases. But a recent review by Prof. Irvingfound specific DNA anomalies that 'tend' to occur in
Gottesman of the University of Minnesota in themost patients with certain diseases. But they've failed
journal Human Molecular Genetics casts serious doubtto check if these DNA anomalies also exist in healthy
on the 'DNA causes disease' theory.people. What this study has shown is that these DNA
The review concerns identical twins (who, as weanomalies DO exist in healthy people and haven't
know, have identical DNA). What Prof. Gottesmancaused them to get sick.
found is quite intriguing. Schizophrenia, often thoughtWe've been led to believe that we're doomed if we
to be caused by DNA, is only 50% 'concordant'. Inhave faulty DNA. What this study shows is that this
other words, in only half of the twin pairs does themyth is flat out not true. DNA does not have the
second twin have the disease if the first one does.power we've been led to believe it has. If it did, then
To put it another way, out of 100 pairs of twins,if one twin had a supposed 'DNA disease', then in
where at least one twin has schizophrenia, in only half100% of the cases, so would the other twin. Multiple
of the pairs of twins do both twins have the disease.sclerosis only had a 25% concordant rate. In other
In the other 50 pairs of twins, only 1 out of the 2words, in 75% of twins, only one twin had the
twins has schizophrenia. This is startling news.disease; the other twin was perfectly healthy.
What does this mean? We are not the NewtonianWhy didn't both twins get these diseases? Scientists
machines that many scientists think we are. Thedon't know, but one thing is for sure. DNA does not
common thought among geneticists is that thehave the power that we once thought it had. Prof.
human body is built like a car. If you put faulty wiringGottesman notes that scientists sometimes have
in a car, the windows won't roll up.blind spots that prevent them from seeing the truth.
However, what this study proves is one of twoThe belief that certain DNA sequence anomalies
things:cause disease "may be one such blind spot among
One, either DNA isn't the cause of these diseases.geneticists.
Or two, faulty DNA does not have to lead to a