University of Michigan Kellogg Eye Center | 1000 Wall Street, Ann Arbor, MI 48105 | 734.763.8122
Copyright © Regents of the University of Michigan
|
|||
|
|
 |
|||||||||||||||
| Microarray Accelerates Genetic Research At Kellogg  Now that the map of the human genome has been published, scientists all over the world are ready to roll up their sleeves and find out how genes actually work.A new technology called a gene microarray will allow scientists to analyze thousands of segments of DNA at once, yielding a vast amount of information about genes. Kellogg has one of the first vision research laboratories in the country with this technology. What Is a Microarray? It’s a piece of equipment that uses a robot and a computer to compare DNA we understand with DNA we do not. Every cell in our body contains the same 6 feet of DNA. But only a small portion is active (scientists call thisactivity expression) in any one cell. If our cells all contain the same genetic material, how does each group of cells know what its job is and how to carry it out? Why are genes expressed in the proper place? Our eye cells allow us to see, our brain cells enable us to think and remember, our heart cells know their job is to keep the heart pumping. How do they know?
It’s the same with genes. A DNA sequence controls the function of cells. When there is a variation in the sequence, the expected function does not occur as it should. The change can be harmless or it can be helpful (as in creating a protective effect), or it can cause a significant problem. These sequence variations often work together to our disadvantage. They can increase our risk for any number of problems — cancer, schizophrenia, heart disease, or, in the affliction our scientists deal with, blindness. This latter risk, this possibility that we will lose vision, is amplified by the fact that we are all living longer. As we age, many things in our body wear out. Vision loss can be an outcome of the aging process or of cells gone awry for other reasons. Whatever the cause, blindness is a sad fact of life for millions of people. Kellogg Eye Center scientists are working to understand the genetic causes of blinding eye diseases like macular degeneration, which affects older people. Or retinoschisis, which blinds youngsters. Or glaucoma, which threatens the vision of millions and is the leading cause of blindness in African Americans. Once we can identify what’s gone wrong in the gene we will be a big step closer to designing an effective therapy. How Does the Microarray Work? A robot dips a set of pins into tiny wells filled with strands of DNA material. Then it carries the pins to wafer-thin glass slides where it deposits its cargo in a precise arrangement. The slide is now a DNA chip. After the pins are washed and dried the robot brings them to another set of wells where they will be dipped into more microscopic vats of DNA. Tens of thousands of these specks can fit on one small slide in about one square inch. What Is the Chip For? The DNA chips allow scientists to study many different tissues at once. They can compare retinal tissue from a newborn to retinal tissue from a 90-year-old. Or they can compare tissue from a child with retinoschisis to tissue from that child’s sister, who does not have the disease. Fluorescent dyes attached to certain molecules on these study samples light up when scanned by a special laser. The different colors and intensities give scientists information about the genes. Why Do We Study Genes? A change in genetic sequence can set off a chain of events that may lead to loss of vision. We need to find a window of opportunity along this chain where we can intercept the process and prevent vision loss. Scientists call this opportunity a target. The microarray will help us identify a target that will lay the groundwork for future treatments. |
|
University of Michigan Kellogg Eye Center | 1000 Wall Street, Ann Arbor, MI 48105 | 734.763.8122
Copyright © Regents of the University of Michigan |