A biomarker, or biological marker, is in general a substance used as an indicator of a biological state. It is a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. It is used in many scientific fields.
In medicine, a biomarker can be a traceable substance that is introduced into an organism as a means to examine organ function or other aspects of health. For example, rubidium chloride is used as a radioactive isotope to evaluate perfusion of heart muscle. It can also be a substance whose detection indicates a particular disease state, for example, the presence of an antibody may indicate an infection. More specifically, a biomarker indicates a change in expression or state of a protein that correlates with the risk or progression of a disease, or with the susceptibility of the disease to a given treatment.
Biochemical biomarkers are often used in clinical trials, where they are derived from bodily fluids that are easily available to the early phase researchers. A useful way of finding genetic causes for diseases such as schizophrenia has been the use of a special kind of biomarker called an endophenotype.
In cell biology, a biomarker is a molecule that allows for the detection and isolation of a particular cell type (for example, the protein Oct-4 is used as a biomarker to identify embryonic stem cells).
Geology and astrobiology
A biomarker can be any kind of molecule indicating the existence, past or present, of living organisms. In the fields of geology and astrobiology, biomarkers, versus geomarkers, are also known as biosignatures. The term biomarker is also used to describe biological involvement in the generation of petroleum.
A biomarker can also be used to indicate exposure to various environmental substances in epidemiology and toxicology. In these cases, the biomarker may be the external substance itself (e.g. asbestos particles or NNK from tobacco), or a variant of the external substance processed by the body (a metabolite). (See also: Bioindicator.)
- Biomarker discovery
- Biomarkers (journal)
- Biomarker insights - a journal
- Molecular marker
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Biomarker — für die Medizin oder Biologie sind messbare Produkte von Organismen, die als Indikatoren z. B. für Umweltbelastungen oder Krankheiten herangezogen werden. In der Geologie versteht man unter Biomarkern organische Substanzen, die in Sedimenten … Deutsch Wikipedia
biomarker — A substance sometimes found in the blood, other body fluids, or tissues. A high level of biomarker may mean that a certain type of cancer is in the body. Examples of biomarkers include CA 125 (ovarian cancer), CA 15 3 (breast cancer), CEA… … English dictionary of cancer terms
biomarker — noun Date: 1982 a distinctive biological or biologically derived indicator (as a metabolite) of a process, event, or condition (as aging, disease, or oil formation) … New Collegiate Dictionary
biomarker — bi·o·mark·er (bīʹō mär kər) n. Medicine 1. See marker. 2. A specific physical trait used to measure or indicate the effects or progress of a disease or condition: Biomarkers of aging include thinning of the hair and diminished elasticity of the… … Universalium
biomarker — noun ˈbaɪoʊˌmɑɹkɚ A substance used as an indicator of a biological state, most commonly disease … Wiktionary
Biomarker — A biochemical feature or facet that can be used to measure the progress of disease or the effects of treatment. * * * bio·mark·er bī ō .mär kər n a distinctive biological or biologically derived indicator (as a biochemical metabolite in the body) … Medical dictionary
biomarker — bio·marker … English syllables
biomarker — /ˈbaɪoʊmakə/ (say buyohmahkuh) noun Medicine a molecule specifically associated with a particular disease, the detection of which provides an early indication of the onset or status of the disease … Australian English dictionary
Biomarker — Bio|mar|ker (Biologie, Medizin Substanz, die in einem Organismus Schädigungen durch Krankheit o. Ä. anzeigt) … Die deutsche Rechtschreibung
biomarker — ˌ noun Etymology: bi (II) + marker : a distinctive biological or biologically derived indicator (as a biochemical metabolite in the body or an organic compound in rock) of a process, event, or condition (as aging, disease, or oil formation) … Useful english dictionary