Science and Disease

Cancer is one of the most infamous diseases in the world. According to the American Cancer Society, half of all men and one-third of all women will develop cancer during their lifetime. One of the most important jobs of scientists today is to study diseases like cancer in order to determine how to best treat patients, and possibly cure the disease. The best way for a scientist to learn more about a disease is not merely to study the symptoms, but to see what's happening in a person's cells and with their proteins. You see, if the cell is a factory, then proteins are the workers that make the factory, or the cell, function. If even a single type of protein or "worker" is messed up, then our cells cannot work properly and we will develop a disease. For example, cancer is caused by out of control cell growth that results in a tumor. This cell growth is caused by certain proteins not working properly - such as proteins responsible for repairing the cell or for limiting growth. The more we understand about how these proteins work, the closer we are to curing cancer! (image from www.chicanol.com)


Why Study Fruit Flies?

So what does this all have to do with fruit flies? Well, fruit flies are actually more similar to humans that you would think. In fact, they share nearly 60% of our genes! This means that flies also have a lot of similar proteins that carry out the same functions as they would in human cells. For example, one protein in particular that we share with flies is called the BLM protein. This protein, which is responsible for keeping our DNA safe, is messed up in patients with Bloom's syndrome. This causes them to have a LOT of other mutated proteins, and eventually leads to multiple types of cancers. Scientists can study this protein in flies and apply their knowledge to humans! This is why fruit flies are called model organisms; they're used as a model for human diseases. Besides having similar genes and proteins to humans, they're also great models for a few more reasons:

  1. Short Growth Time - Fruit flies grow from egg to adult fly in about 8-10 days (depending on the temperature).  Compare that to humans, which require at least 9 months to even be born (let along become an adult!).  If we did research on humans, it would take scientists years and years to make any sort of progress.
  2. Small Size, Simple Care - Humans cannot be stored in small containers that you can put on a shelf. Fruit flies, however, do quite well in this environment and also do not require much food or supervision.
  3. Chromosomes - Fruit flies have a smaller amount of chromosomes than humans.  The chromosomes also have distinct patterns; this makes it easier to understand where genes are than it would be in humans2.
  4. Body of Research - We know a lot about fruit flies already. Scientists have been doing research with them for over 100 years!  This means we are already extremely familiar with the best way to care for them (ex: what temperature and food allows them to grow the best) and how their genes work.  The more we know, the further our research can go.

Citations:

  1. http://news.bbc.co.uk/2/hi/science/nature/647139.stm
  2. http://genome.wellcome.ac.uk/doc_WTD020807.html