With the completion of the Human Genome Project, we have learned that the word “normal” no longer has meaning when it comes to a person’s genetic makeup. Genetic variations occur in great numbers in our genome (our total genetic makeup). We are all unique, not only in our personalities and appearance, but in our genotype as well.
Scientists continue to work on ways to better understand the structure of our genetic makeup, which could allow for important advances in the prevention and treatment of many diseases. Gene therapy is an approach to treating potentially lethal and disabling diseases that are caused by single gene deficiencies. With specialised techniques, gene expression can be manipulated to correct the problem in the particular patient, although the correction will not be passed along to the offspring of that patient. That is, corrections are made at the DNA molecule level to compensate for the abnormal gene so that the detrimental symptoms of the disease are not expressed in the patient. This type of treatment is still highly experimental. Clinical trials are being conducted to see if gene therapy can be used to develop treatments for other diseases not caused by single gene mutations such as cancer, heart disease, and AIDS.
Further advances in technology and molecular biology laboratory techniques have led to the "gene chip" or microarray - which allows many genes to be examined together instead of one at a time as previously. Using these gene chips, researchers can look for molecular indicators of disease even before the disease presents itself and the patient becomes symptomatic. Newer techniques for DNA sequencing called next generation sequencing allows much faster and cheaper sequencing of large portions of, or even the entire genome.
Further advances in genetic testing will eventually replace many older methods of predicting prognosis, help to identify those patients who will respond to a particular therapy and help guide further research into these therapies. Recent advances are also helping to increase our understanding of some complex cancers, such as multiple myeloma, lung cancer and lymphoma. Without a doubt, there will be more and more advances in genetic research that will impact the laboratory tests available to all patients for detection and treatment of a variety of diseases.
This article was originally written by Barbara Border, PhD. (Associate Professor and Program Director, Molecular Pathology. Texas Tech University Health Sciences Center, Lubbock, TX) for Lab Tests Online US. It has been modified for the LTO Australasia site.