About a month ago, the 2 billionth base pair of human DNA was sequenced. There are only about 1.2 billion pairs to go. After the last pair is sequenced, scientists will have the actual code for the sum total of human DNA.

The data, when compiled, will consist of a string of 3.2 billion A’s, Cs, Gs, ant Ts. If you were to display it, the code would look something like “GATAATTACGGGA,” that would extend on and on for quite some time.

Work on the Genome project began in 1988 and the human genome was originally scheduled to be sequenced by 2005. The current timetable expects a “working version” to be released this summer, with 90 percent of the base pairs sequenced at 99.9 percent accuracy. When finished, the information will provide an invaluable resource for all biologists and geneticists who work with humans.

In the public mind, the DNA of an organism is often thought of as being the “blueprint” for that organism. This is basically true although slightly misleading.

The letters of the genetic code stand for molecules that are intertwined into the familiar double helix of the DNA strand.

When “read” through appropriate mechanisms, DNA is translated into proteins. By itself, this is interesting but not terribly mind-blowing. It is the interaction between various genes (bits of DNA that code for proteins) that make all life possible.

As much of a milestone as the human genome is, the complete understanding of human genetics is probably too complicated to ever understand fully. Scientists may soon know the order of base pairs, but more than 95 percent of the genome is non-coding, meaning that it is never translated into proteins of any kind. Most of the letters are “junk,” that serve no known purpose.

Even when the genes are identified, it is not yet possible to determine what kind of protein the gene codes for, let alone the biological role that the gene and protein plays in the human body.

On the subject of biotechnology, genetic treatments have been or are being developed for many disorders. If doctors can identify a genetic abnormality in a fetus, he or she can provide treatment to compensate.

In the future, it may even be possible to alter the genes of the fetuses, in order to “correct” problems. The capability to do these things opens up a multitude of thorny ethical issues. Scientists understand the genetic basis of eye and hair color and have a rudimentary grasp of height, body build and various athletic abilities. It may one day be possible to virtually “design” babies by picking and choosing genes. The scenario is often discussed in bioethics circles and policy debates.

Although this is possible, there is good reason to believe that scientists will never have a good enough grasp of genetics to make baby-designing possible.

Although we may understand the genetic basis of height, weight and athletic build, the complex and subtle interactions between genes may present an insurmountable problem.

In agriculture, for example, genes that confer cold-resistance have been successfully placed into corn plants.

One unexpected side effect of this gene is that it makes the corn plants brittle, so that they sometimes blow over in a strong wind. The kind of experimenting that makes genetic engineering work in agriculture is obviously not going to happen in the case of humans.

Even with the current state of knowledge, it is obvious that the sequencing of the entire human genome will revolutionize the medical and biotechnology industries. Biology has always been a science that deals with interesting philosophical implications.

Genetics is perhaps even more so. What is especially interesting is what the science of genes can tell us about ourselves.

Take the subject of human brains. Brains are constructed according to the “instructions” in DNA, even in humans. Even though this is the case, the development of the human brain is dependent on many factors.

In addition to the obvious need for nutrition, oxygen and such, human brains develop according to the stimulus that the child goes through. As a child learns, neurons actually grow and form new connections, connections which are the basis of thought and learning.

Genetics play an important role, however. Autism has a relatively simple genetic basis. All the symptoms associated with Down Syndrome are caused by having three copies of the 21st chromosome, instead of just two.

Most people would have no problem with genetic treatments for a fetus with a damaging and preventable illness.

But what about parents who want to “improve” their child by slightly tweaking genes involved with intelligence or athletic ability? Where shall the line be drawn between “treatment” and “tampering?”

Should employers be allowed to screen their employees for productivity-draining genetic conditions or susceptibilities? Should insurance companies be able to demand genetic tests of those they insure?

The new possibilities created by biotechnology and genetics have great promise but have the potential to do harm as well. Certainly, these issues demand public scrutiny and debate, lest policy decisions be made by corporations and the politicians they buy.

As many prior examples have shown, this rarely leads to a healthy situation.

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Elton Wong is a junior in biology and philosophy from Ames.