HD Glossary

Note: Some words can have differing definitions depending on the context in which they are used. The definitions presented here are the ones that best apply to the words as they are used. HDSA is grateful to the Stanford Hopes website for their contribution and maintenance of this glossary.

 

 

F
  • FAD - Abbreviation for Flavin-adenine dinucleotide.
  • FALS - Familial Amyotrophic Lateral Sclerosis. This is the form of Amyotrophic Lateral Sclerosis that is linked to a genetic mutation on chromosome 21. A protein called superoxide dismutase (SOD) that normally functions as an antioxidant acquires a mutation that makes the it nonfunctional.
  • false positives - Also known as Type 1 errors, occur when we observe a difference that in truth is not actually there. In the R&D pipeline, this could occur when experimental results suggest that a drug interacts with a biological target, where in fact it does not.
  • familial dysautonomia (FD) - An inherited disorder that primarily causes dysfunction of the autonomic and sensory nervous systems as a result of an incomplete development of the nerve cells of these systems. The autonomic nervous system regulates involuntary bodily functions, such as regulation of blood pressure and body temperature and normal swallowing and digestion. The sensory nervous system regulates protective reactions to pain, perceptions of hot and cold, and taste.
  • family systems theory - A recent theory that attributes the weakening of a couple and/or family relationship to the mounting tension during the waiting period before receiving predictive testing results.
  • fast track product - A potential drug in development that is believed to meet an unfulfilled medical need and is required urgently, so that the process of testing in clinical trials and FDA evaluation of the results is sped up.
  • fat-soluble - Capable of being dissolved in fat.
  • fats - One of the three main classes of foods and a source of energy in the body. Fats help the body use some vitamins and keep the skin healthy. They also serve as energy stores for the body. In food, there are two types of fats: saturated and unsaturated.
  • fatty acid - A class of compounds that contain a long chain composed of hydrogen and carbon atoms. In general, fatty acids refer to any compound derived from the breakdown of fats.
  • FDA - Food and Drug Administration. A federal United States agency that, among other responsibilities, makes sure that foods, medicines, cosmetics, and medical devices are safe and/or effective.
  • feedback loop - a feedback loop is where two or more molecules mutually act upon one another in a cycle. It usually is meant to allow a biological process to efficiently slow down or speed up, depending on the type of feedback loop
  • fermentation - One process by which carbon-containing compounds are broken down in an energy yielding process. Fermentation occurs during times of low oxygen supply and is therefore known as a type of anaerobic respiration.
  • fertility - The number of live births per parent; the capacity to conceive and generate live offspring.
  • fetal neurons - Cells in a fetus that will eventually develop into neurons.
  • fetus - In human beings, the unborn young from the eighth week of pregnancy to birth; an organism in the stage of development that follows the embryonic stage.
  • fibril - A small filament or fiber.
  • fibrinogen - A protein present in blood plasma that causes blood clots when the stress response is activated.
  • fitness (reproductive fitness) - Measure of the relative survival and reproductive success of a given individual or characteristic compared to others.
  • fixation - The chemical preservation of cells or tissues.
  • Flavin-adenine dinucleotide (FAD) - Coenzyme sythesized from riboflavin. FAD acts as an electron carrier in energy metabolism.
  • Flavin-mononucleotide (FMN) - A coenzyme synthesized from riboflavin. FMN acts as a component of Complex I of the electron transport chain.
  • flavins - A group of molecules with a unique ring structure. FMN and FAD are part of the flavin group of molecules.
  • flavonoids - A constituent of Ginkgo biloba extract that has been found to reduce the level of free radicals by decreasing cell membrane lipid peroxidation.
  • flax oil - A type of oil derived from flax plant that contains a great amount of omega-3 fatty acids.
  • fluoxetine - A member of the class of drugs known as selective serotonin reuptake inhibitors (SSRIs) . It is normally used to treat depression and obsessive-compulsive disorder, but may also be helpful in improving motor impairment and cognitive functioning in people with HD.
  • FMN - Abbreviation for Flavin-mononucleotide.
  • fMRI - Stands for "functional magnetic resonance imaging." This technique uses magnetic fields to measure oxygen use by nerve cells in the brain. It allows researchers to determine which specific areas of the brain are most active during a task.
  • folate - The naturally occurring version of folic acid.
  • folding - The process by which a chain of amino acids is modified to reach the final shape of the protein.
  • folic acid - A B vitamin essential for production of new cells and important for the metabolism of homocysteine.
  • formulation - When a drug is made up of multiple compounds, the formulation describes the specific recipe for the drug, including which compounds are included and in what proportions.
  • free radicals - Atoms or molecules that are highly reactive with other cellular structures because they contain unpaired electrons; free radicals can be very harmful to cells.
  • French paradox - The finding that the rate of heart disease in France is lower than observed in other industrialized countries, despite the fact that the country’s diet is rich in saturated fats.
  • frequency - The proportion of a population falling into a particular category.
  • frontal cortex - Part of the brain generally thought to be where higher level thinking, planning, and goal formulation take place.
  • frontal lobes - One of the four lobes of the brain. It is divided into motor, pre-motor and pre-frontal areas. The pre-frontal area is responsible for many cognitive functions.