Glossary of Acronyms and Terms
This glossary of acronyms and terms related to genetic testing will help you avoid drowning in alphabet soup at this site. The glossary on this page is strictly in reference to the topics discussed on this site and is by no means comprehensive. The National Human Genome Research Institute (NHGRI), one of the arms of the National Institute of Health (NIH), has developed a comprehensive Talking Glossary of Genetic terms, and has also developed a 'Talking Glossary of Genetics' for mobile devices.
ACCE: ACCE took its name from the four components of evaluation often used for medical treatments: analytic validity, clinical validity, clinical utility, and associated ethical, legal, and social implications. ACCE serves as a model for developing a systematic method for evaluating data about emerging genetic tests. Supported by the CDC Office of Genomics and Disease Prevention, the project researched five genetic tests between 2000 and 2004.
AHRQ: Agency for Healthcare Research and Quality (AHRQ) is a leading federal agency charged with improving the quality of health care for all Americans. As one of 12 agencies in the Department of Health and Human Services, AHRQ supports research that will improve health care and promote evidence-based decision-making.
Biochemical testing: Form of genetic testing that measures an analyte, rate of a chemical reaction (enzyme) to the presence of a protein, or the structural change of a protein. The level or rate that is analyzed in this test can indicate gene variations and thus a genetic disorder or a disease. For example, the protein levels indicate whether or not the gene is working normally. These types of tests are used for newborn screening. For example, this screening can detect infants who have metabolic conditions such as phenylketonuria (PKU). (Source: National Human Genome Research Institute)
A biochemical test can also analyze an analyte, which is a substance in the body that can be measured or defined in some way for diagnostic purposes. The presence of a significantly larger or smaller than normal quantity of an analyte may be indicative of a genetic disorder.
The last kind of biochemical genetic test is an enzyme assay. It measures the rate of a chemical reaction in the presence of a protein that facilitates that reaction (enzyme). The activity of the enzyme is quantified in order to assess genetic disease or carrier status of a specific disease related to this reaction.
CDC: The Centers for Disease Control and Prevention (CDC) is one of the 13 major operating components of the Department of Health and Human Services (HHS). HHS is the principal agency in the United States government for protecting the health and safety of all Americans and for providing essential human services, especially for those people who are least able to help themselves.
Carrier: An individual who has a recessive, disease-causing gene, which does not affect him or her, but could affect the individual's children.
Chromosome: A structure consisting of DNA and protein organized into thread-like filaments found in the nucleus of the cell. Different organisms have different numbers of chromosomes.
Cochrane Collaboration: An international nonprofit organization dedicated to making up-to-date, accurate information about the effects of health care readily available worldwide. Based in Oxford, England, Cochrane produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions.
CETT: The Collaboration, Education, and Test Translation (CETT) Program for Rare Genetic Diseases is a pilot program to promote new genetic test development and better understanding of each rare disease. Through CETT, researchers allied with patient advocacy groups can apply to the National Institutes of Health for funds to translate clinical tests for rare genetic diseases from research to clinical laboratories.
Cytogenetic testing: Genetic testing that involves the examination of chromosomes. Chromosomes are structures in the nucleus of a cell that contain DNA. A chromosomal test looks at features of a person's chromosomes, including their structure, number, and arrangement. These tests look for changes, such as pieces of chromosomes being switched or being in a different location. (Source: National Human Genome Research Institute)
One method of cytogenetic tests is the Fluorescence In Situ Hybridization (FISH) which is a technique in which a known submicroscopic piece of a chromosome is labeled with fluorescence and then mixed with the cell nucleus to be tested. This labeled probe then attaches to its match within the cell and can be viewed with special lighting. In this way, FISH can be used to test for missing or additional chromosome material. (Source: GeneTests)
Direct testing: Genetic testing that includes the direct examination of the DNA or RNA that makes up a gene. This kind of test is looking for signs of a disease or disorder in DNA taken from a person's blood, body fluids or tissues. The tests can look for large changes, such as a gene that has a section missing or added, or small changes, such as a missing, added, or altered chemical base within the DNA strand. Other important changes can be genes with too many copies, genes that are too active, genes that are turned off, or those that are lost entirely.
Direct DNA testing detects a disease-causing change (mutation) in a gene known to cause a particular disorder. Direct DNA analysis can be accomplished when the gene in question is known and gene changes can be found and interpreted. (Sources: National Human Genome Research Institute and GeneTests).
Direct-to-Consumer Genetic Tests: DTC are tests marketed via television, internet and print media directly to consumers. DTC tests are also called at-home genetic tests and typically do not involve healthcare providers, genetic counselors or clinicians.
EGAPP: Evaluation of Genomic Applications in Practice and Prevention (EGAPP), a model project to adapt and implement methods for thorough, impartial evaluation of genetic tests and other genomic applications.
EBM: Evidence-based Medicine (EBM) is an approach to medical practice that stresses the systematic search for and use of relevant literature and studies. Along with evidence-based review (EBR) and evidence-based practice (EBP), EBM constitutes a movement in the medical field to ensure that medical care and research makes use of good, current science and discounts irrelevant, outdated or commercially compromised literature and studies. While the Centre for Evidence-Based Medicine leads the movement in Britain, the Agency for Healthcare Research and Quality promotes evidence-based practice in the U.S. and Canada through several Evidence-based Practice Centers. Evidence-based review is important in the growing field of genomics, where gathering reliable data on a flood of new applications still in development is a major challenge.
Gene: Unit of heredity made up of DNA and containing the code to make proteins. Every person has two copies of each gene, a copy inherited from each parent. The Human Genome Project estimates humans to have between 20,000-25,000 genes.
Genetic tests: A genetic test is the analysis of human DNA, RNA, chromosomes, proteins, or certain metabolites in order to detect alterations related to a heritable disorder. This can be accomplished by directly examining the DNA or RNA that makes up a gene (direct testing), looking at markers co-inherited with a disease-causing gene (linkage testing), assaying certain metabolites (biochemical testing), or examining the chromosomes (cytogenetic testing) (Source: GeneTests)
Genomic applications: Practices used in the clinic and in healthcare settings that may help increase our knowledge of how genes, environmental factors, and a person's lifestyle habits and behavior influence their risk of disease and response to medical treatment. Some examples of genomic applications include genetic testing and making a family health history.
Human Genome: The human genome is made up of DNA, which has four different chemical building blocks. These are called bases and abbreviated A, T, C, and G. In the human genome, about 3 billion bases are arranged along the chromosomes in a particular order for each unique individual. To get an idea of the size of the human genome present in each of our cells, consider the following analogy: If the DNA sequence of the human genome were compiled in books, the equivalent of 200 volumes the size of a Manhattan telephone book (at 1000 pages each) would be needed to hold it all. (Source: Human Genome Program, http://www.ornl.gov/sci/techresources/Human_Genome/faq/faqs1.shtml)
Human Genome Project: Begun formally in 1990, the U.S. Human Genome Project was a 13-year effort coordinated by the U.S. Department of Energy and the National Institutes of Health. The project originally was planned to last 15 years, but rapid technological advances accelerated the completion date to 2003. Project goals were to:
- identify all the approximately 20,000-25,000 genes in human DNA
- determine the sequences of the 3 billion chemical base pairs that make up human DNA
- store this information in databases
- improve tools for data analysis
- transfer related technologies to the private sector, and address the ethical, legal, and social issues (ELSI) that may arise from the project.
Linkage testing involves the study of several family members in order to infer the presence of a disease-causing change (mutation) in a gene by identifying genetic DNA markers that are co-inherited with the gene of interest (Source: GeneTests)
Non-genetic factors: Influences for genetic changes and gene mutations that lead to disease. These factors are not hereditary; rather, they are such lifestyle practices and habits, such as diet, exercise, and smoking.
OPHG: The Office of Public Health Genomics (OPHG) was formerly the Office of Genomics & Disease Prevention (OGDP) at the Centers for Disease Control and Prevention. Established in 1997, the CDC's Office of Public Health Genomics was created to improve population health and prevent disease through the application of genomic information.
NWCGPH: The Northwest Center for Genomics and Public Health is also known as the University of Washington Center for Genomics and Public Health (UWCGPH). The Center works to integrate genomics into public health. For the EGAPP project, the Center is also involved in disseminating findings and coordinating stakeholder involvement.
Office of Rare Diseases, National Institutes of Health (NIH): http://rarediseases.info.nih.gov/ Two agencies at the National Institutes of Health (NIH), the National Human Genome Research Institute (NHGRI) and the Office of Rare Diseases (ORD), created the Information Center to help people find useful information, in English or Spanish, about genetic and rare diseases. There are more than 7,000 rare diseases. A disease is rare if fewer than 200,000 people in the United States have it. About 25 million Americans have a rare disease. Many rare diseases are caused by changes in genes and are called "genetic diseases."
Pharmacogenomics: Pharmacogenomics is the study of how an individual's genetic makeup or inheritance affects the body's response to certain drugs. Environment, diet, age, lifestyle, and state of health all can influence a person's response to medicines, but understanding an individual's genetic makeup is thought to be the key to creating personalized drugs with greater efficacy and safety. Pharmacogenomics combines traditional pharmaceutical sciences such as biochemistry with annotated knowledge of genes, proteins, and single nucleotide polymorphisms.
Population-based intervention: Taking advantage of a large demographic or community to prevent disease or to uncover gene mutations or susceptibility to gene mutations. For example, a universally used vaccine like the polio vaccine is a population-based intervention to prevent the reemergence of polio in the US. But screening a particular population to see whether there are common gene mutations, for example, is another kind of intervention used by scientists. They can uncover particular gene mutations by studying a particular population. For example, scientists studying AIDS found that certain high-risk groups like prostitutes in Nairobi, Kenya, KENYA did not develop HIV and appear to be HIV-resistant. By studying this particular population, these scientists hope to uncover what exactly makes these women resistant to the virus, with the hope of eventually being able to develop a potential vaccine to stop the spread of HIV.
Protein: Proteins are macromolecules made up of amino acids that are vital in facilitatating biological processes and function. Proteins are synthesized when the gene specific to a protein is activated.
Rare genetic disorders: A particular disorder might be described as "running in a family" if more than one person in the family has the condition. Some disorders that affect multiple family members are caused by gene mutations, which can be inherited (passed down from parent to child). Other conditions that appear to run in families are not inherited. Instead, environmental factors such as dietary habits or a combination of genetic and environmental factors are responsible for these disorders.
It is not always easy to determine whether a condition in a family is inherited. A genetics professional can use a person's family history (a record of health information about a person's immediate and extended family) to help determine whether a disorder has a genetic component. (Source: Genetics Home Reference, U.S. National Library of Medicine)
RNA: ribonucleic acid. This macromolecule is involved when the gene is activated. It encodes and carries genetic information from the DNA (in the nucleus) to guide protein synthesis in the cell's cytoplasm.