DNA Damage - Do We Think About It? It's Important That We Prevent It!

DNA damage is going on in our body right this minute and we don’t even know it. It is something we just don’t think about. But the consequences of it are very serious and life threatening. DNA is material that governs inheritance of eye color, hair color, stature, bone density and many other human traits. DNA is a long, but narrow string-like object. A one foot long string or strand of DNA is normally packed into a space roughly equal to a cube 1/millionth of an inch on a side. This is possible only because DNA is a very thin string.

Your body constantly reacts with oxygen as you breathe and your cells produce energy. As a consequence of this activity, highly reactive molecules are produced known as free radicals.

Free radicals interact with other molecules within cells. This can cause oxidative damage to proteins, membranes and genes.

Oxidative damage has been implicated in the cause of many diseases such as cancer and Alzheimer's and has an impact on the body's aging process.

Our body’s cells each contain a complete sample of our DNA. One cell is roughly equal in size to the cube described above. There are muscle cells, brain cells, liver cells, blood cells, sperm cells and others. Basically, every part of the body is made up of these tiny cells and each contains a sample of DNA identical to that of every other cell within your body. There are a few exceptions. For example, our red blood cells lack DNA. Blood itself can be typed because of the DNA contained in our white blood cells.

There are many genes that can become mutated to make a cancer cell more 'successful' at surviving in the body. For example, some genes make proteins that allow the cell to travel down blood vessels, allowing a cancer cell to spread to other parts of the body. Others prevent damaged cells from being attacked by the body's immune system. We are learning more and more all the time about how cancer cells live and grow in the body - with every new piece of information, we uncover another potential way to prevent, diagnose or treat cancer. But why haven't they found a cure yet? Why haven't they found a way to prevent cancer? DNA damage is an extremely common event in a cell's lifetime. The machinery that copies DNA when a cell divides is not 100% efficient. This means that tiny errors accumulate in our cells over our lifetimes.

On top of this, the life-sustaining chemical reactions that occur naturally in our cells generate harmful by-products, and these can cause DNA damage. So merely ‘being alive’ can cause DNA damage and, potentially, cancer.

To make matters worse, our everyday surroundings are full of things, such as background radiation, sunlight and tobacco smoke, which constantly damage the DNA in our cells. As a result of this continuous bombardment, some studies have estimated that the DNA in a single human cell gets damaged over 10,000 times every day. Wow! What can we do? How do we protect our body from this daily damage?

So why don't we constantly develop cancer?

Thankfully, cells have evolved many complex mechanisms to detect and repair DNA damage, and most of the time a cell repairs its damaged DNA without a problem. But, just like the machinery that copies DNA, a cell's repair machinery is not 100% efficient and not every single error is corrected.

So, as a back up, to prevent cancer occurring, there are systems that cause a damaged cell to commit suicide if the DNA damage is too severe. DNA repair and apoptosis (cell suicide) have been the subject of huge amounts of research. Occasionally, despite all of these safety nets, the cell’s repair machinery fails to correct the DNA damage, but doesn't trigger the cell's suicide apparatus. And this is when cancer can occur. In fact, some of the most harmful cancer-causing mutations are mutations in the genes that regulate DNA repair and apoptosis. It is now thought that developing cancer is as much to do with the failure to repair DNA damage as it is to do with acquiring the mutations in the first place.

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