Food for thought about how to live healthy!

Posts tagged ‘genes’

DNA: Don’t Get It Twisted

In the field of medicine, DNA and genetics is a relatively new concept. The first pictures of DNA were taken just over 50 years ago. Now, people use DNA for everything: engineering crops, selective breeding of livestock, solving crimes, medical therapy. But what exactly is DNA? What is it made of? How does it work? What does it look like?

Well Italian scientists have captured the most high-resolution photo of DNA to date, and it looks something like THIS:

A high resolution photo of DNA taken by Italian scientists. It was captured by dehydrating a strand of DNA and using an electron microscope.

It kind of looks like a hairy caterpillar.

Some of you are saying “Didn’t scientists take pictures of DNA in the 50’s?” While we have had images of what DNA may look like, we haven’t really been able to look at DNA directly. Old pictures were taken with X-Ray techniques, which use light to reflect the image of DNA. It’s like trying to determine what a hand looks like by looking at its shadow. Well with the electron microscope, used to take the picture above, scientists can fire electrons at the DNA to determine it’s really shape. We can even see the double helix base pairs! How cool is that?

DNA stands for deoxyribonucleic acid. It is a double helix structure with four base pairs, adenine, guanine, thynine, and cytosine! The sequence of these base pairs determines how the DNA functions! For example, take the genetic sequence for eye color. A sequence of A-C-T-C-G-A might determine blue eyes while G-C-A-T-A-C might cause green eyes. Of course, that was just a short version. In reality, genetic code contain billions of base pairs and sequences that are responsible for EVERYTHING our body does. Much like a computer is programmed with simple 0110101 codes, our DNA functions the same way. And like a fingerprint, not one person’s genetic sequence is the same. Even identical twins have two different genetic makeups.

DNA resides in each of our cells in a structure called the nucleus. The nucleus is like the brain of the cell, and the cell functions as the DNA tells it to. The cell reads DNA via an intricate process called DNA Transcription and Translation. Sometimes, there is something wrong with the DNA. It may be damaged, incomplete, or unable to be processed. That’s when we have genetic disorders, such as heterochromia or red hair (yes, red hair is a genetic mutation of blonde hair!). When DNA becomes corrupt and damaged, whether it’s through age or an environmental factor or it’s just prone to be that way, that’s when cells become malignant and turn into cancer. From how many strands of hair we have to how tall we are, DNA controls it all.

The thing about DNA is it thrives off of diversity. That’s why inbred people were often kind of messed up. When you combine two very similar genetic sequences, the DNA can get confusing for the cell to process thus leading to a myriad of problems. While it’s legal in 19 states and in the District of Columbia to screw your first cousin (it’s also legal to marry them in 6 of those states), it’s generally not a good idea. Research has shown that offspring between first cousins have a 7 to 8 percent chance of developing a genetic disorder like Tay-Sachs or Cystic Fibrosis. Even though Charles Darwin, a guy who knew a thing or two about genetics, married his first cousin, it’s not recommended if you want a healthy baby.

After all, DNA, in it’s double helix shape, is already twisted enough.