Epigenetics Research: Open Access
Open Access

Genetic Biomarker

In genetics, a biomarker (identified as genetic marker) is a DNA sequence that causes disease or is associated with susceptibility to disease. They can be used to create genetic maps of whatever organism is being studied. The identification of new risk factors for specific diseases is an enduring theme in medical research. Advances in molecular biology, genetics, and computational biology are accelerating the pace of this work. The research seeks to increase our understanding of the causes of diseases, but there is also hope that the recognition of new risk factors will lead to improved methods for identifying persons who are in the early stages of, or at high risk for, the diseases of concern. Research has shown, however, that a genomic biomarker must have a much stronger association with the disease outcome than we ordinarily see in etiologic research if it is to provide a basis for early diagnosis or prediction in individual patients. However, even if the literature contains ~150,000 reports of disease-associated molecular markers, there are still very few validated biomarkers of proven and robust clinical utility. At present there is no established, standardized means for validating the association between a marker (or set of markers) and clinical outcomes. 

Biomarker testing is at the center of personalized medicine. The word "biomarker" refers to any of your body's molecules that can be measured to assess your health. Molecules can be obtained from your blood, body fluids, or tissue. Biomarker testing is a group of tests that looks for these molecular signs of health so that doctors can plan the best care. Biomarker testing may also be called "molecular testing" or "genetic testing." Cancer occurs because of abnormal changes within the human genome. The human genome is the plan—like a blueprint—by which our bodies are made and work. It is found in most cells of your body.

The genome is made up of chromosomes. Chromosomes are long strands of DNA (deoxyribonucleic acid) that are tightly wrapped around proteins. DNA is a molecule that is shaped like a twisted ladder. Each step of the ladder is made of either one of two pairs of chemicals. Within the ladder are genes. Genes are instructions to make a product, usually protein.