"One common misconception is that individual humans may carry 'disease-causing' genes, such as a gene for cancer," explains James Erickson, a biology professor at Texas A&M University. "All humans have the same genes, but individual genes have different forms, called alleles, some of which may predispose an individual to a disease."
"Studying the common fruit fly ?Drosophilia melanogaster -- lets us conduct more sophisticated experiments than can be undertaken in humans. These simple organisms can be grown cheaply in test tubes, fed on yeast, corn meal and molasses, yet their embryos, which can be seen with the naked eye, undergo many of the same developmental processes as larger creatures. Thus, they can serve as models, allowing us to observe details we can't see in more complex animals."
To understand cellular differentiation, Erickson and his graduate students have been researching how fly embryos become male or female, a process that occurs over a 30-minute period early in their development and which is similar to the differentiation process for different types of cells, mirroring, for example, the way a liver cell becomes different from a blood cell.
Erickson cautions that there is no direct connection between sexual development in flies and that of humans, but the logic driving their cellular and molecular processes is the same. A paper by Erickson and postdoctoral student Frank Avila detailing their work on such processes has been published in this month's issue of Current Biology, a leading biology journal.
Human females have two X chromosomes in every cell, while human males have an X and a Y chromosome. "Just as in mammals, flies have two 'sex' chromosomes, a X and a Y" he explains. "However, in the fly, unlike in humans, the Y chromos
Source:Texas A&M University