Glossary of Terms

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


A Alzheimer’s Disease The most common form of dementia. It is progressive and the cause is unknown.
Anxiety A term used to encompass worry accompanied with physical symptoms such as headaches and heart palpitations, as well as behavioural symptoms such as avoiding certain situations.
B Bioinformatics The use of technology to collect and analyse biological information such as, genetics and genomes.
Bias Bias is where an association between an exposure and an effect does not equal the true value. Examples of how bias can be introduced into a study are in its design, the selection of the study population and how the data is collected.
Biomarker A change which can be measured in the body which is evidence of exposure to a radiological, chemical or biological agent or the effects of exposure including disease and susceptibility to disease.
C Chromatin DNA that is folded up with an array of proteins.
Chromosome Chromatin is further packaged by folding to form the entity known as a chromosome.
Chromosome abnormalities An unusual number of chromosomes in a cell and/or a structural change within one or more chromosomes such as a deletion, insertion or exchange of chromosomal material.
Chromosome constitution The genetic constitution you are born with and which is (mostly) present in every cell of your body. For a normal human male this is 46,XY and a normal human female it is 46,XX.
Circulatory system The system that moves blood throughout the body. The circulatory system is composed of the heart, arteries, capillaries, and veins.
Cognitive Relates to the mental process involved in knowing, learning and understanding things.
Cognitive Ageing Refers to how our cognitive functioning changes in performance as we age.
Cognitive Assessment A test used to show someone’s cognitive performance. Some assessments test specific cognitive functions, while others test overall cognitive functioning.
Cognitive functioning Mental processes that gather and process information, and allow us to carry out tasks. It includes memory, reasoning, and attention, to name a few.
Cognitive health The ability to clearly think, learn and remember. It also relates to how your brain changes as you age and what you can do to keep your cognitive function at its best.
Cognitive impairment Refers to people who have difficulty in remembering, concentrating and decision making in their everyday lifestyle.
Control group A group of people in a study who resemble the experimental group but who have not experienced the ‘event’ being studied. The same measurements are made in both the experimental and control groups to check for any differences between the two. Ideally, people in the control group should be as similar as possible to those in the experimental group, to make it as easy as possible to detect any differences due to the ‘event’ being tested.
Correlation Interdependence of two or more variable (changeable) quantities such that a change in the value of one is associated with a change in the value of the others. An example is the linear correlation between dose and effect. As you increase dose you increase the effect observed.
Cytogenetics Study of the structure, function and abnormalities of human chromosomes and, how physical changes in chromosome complement influence genetic behavior and clinical effect.
D Dementia An extreme form of cognitive impairment which includes deficits in memory, thought, behaviour, and are unable to perform everyday activities independently.
Deoxyribonucleic acid (DNA) DNA is the molecular basis of heredity. The DNA sequence encodes the genetic information responsible for the development and functions of an organism and, allows for transmission of that genetic information from one generation to the next.The DNA macromolecule is structured as a double-stranded helix held together by weak hydrogen bonds between purine-pyrimidine nucleotide base pairs: adenine (A) paired with thymine (T), and guanine (G) paired with cytosine (C).
Dosimetry The process and or method of measuring the dosage of ionising radiation.
Double strand break (DSB) A type of DNA damage that involves breakage of both DNA strands. This type of damage can cause the cell to die as a mechanism to prevent transmission of genetic damage. Alternatively, the DSB may repair correctly or incorrectly. Incorrect repair may lead to the formation of DNA mutations or structural chromosome aberrations.
E Epidemiology The study of the distribution and determinants of diseases in specific populations.
Exposure worry Bothersome thoughts about potential future events resulting from your possible exposure to radiation or a chemical agent.
F Fluorescence in situ hybridisation (FISH) The process whereby fluorescent dyes are attached to specific regions of the genome, thus aiding the identification of chromosomes and their structure.
G Gene A gene is the basic physical and functional unit of heredity. Genes are made up of DNA.
Genetic Relating to the genes or heredity.
Genetic damage When an agent, such as ionising radiation, causes DNA damage in male or female reproductive (germ) cells, that damage can be transmitted to the next generation (their children).Genetic damage that occurs in any of the other (somatic) cells of the body may also be transmitted to new generations but in this instance, it is passed onto somatic cells in the same person e.g. newly formed blood cells.
Genome The genetic complement contained in the chromosomes of a given organism.
Genomic instability An increased tendency for the occurrence of newly arising, non-clonal, alterations to the genome.
Genotoxic An agent that causes (usually irreversible) damage to or alteration of DNA or chromosomes.
Germline The gamete-producing cells in a sexually reproducing organism (a cell destined to become an egg or in the sperm). The means of which genetic material is passed on to subsequent generations.
Glucocorticoids A group of hormones released during stress. Chronic release of these hormones may impair brain functioning.
H Health-risk behaviours Behaviours such as tobacco smoking and alcohol consumption can be harmful for the body.
Hereditary Biological process responsible for passing on physical traits from one generation to another.
Hippocampus A small area of the brain known to be associated with memory and learning.
Hypertension High blood pressure.
I Ionising radiation Radiation with sufficient energy to eject one or more orbital electrons from an atom or molecule. Ionising radiation can be high energy electromagnetic rays ( X-rays, gamma-rays) or particulate (alpha particles, beta particles, protons).
K Karyotype A laboratory analysis where a person’s full complement of chromosomes are ordered according to a well-established system and examined for abnormalities.
L Lymphocyte A type of white blood cell that is part of the immune system.
M Matched control A control group of individuals selected to resemble an experimental group in all properties except the one under investigation.
Memory Storing and retrieving information or past experiences.
Mental health A person’s condition with regard to their psychological, social and emotional well-being.
Mild Cognitive Impairment (MCI) A disorder in which thinking abilities are mildly impaired, but the person can still perform everyday activities independently.
Mutation A relatively stable change in the DNA of the cell nucleus. Mutations in the germ cells of the body may lead to inherited effects in the offspring.
N Neural cells Also known as neurons/nerve cells, that transform electrical signals from sensory input into motor commands to our muscles.
Nucleus The nucleus houses the cell’s genetic information. This information in encoded in DNA and organised in chromosomes.
P Psychological effect The effect on the mind caused by certain event or factor.
Psychosocial Relating to the interrelation of social factors and individual thought and behavior.
R Radiation Transmission of energy through space and may be able to penetrate various materials.
Radiation exposure Relates to the exposure to radiant energy or to the particles emitted in the transfer of radiant energy, for instance the particles and gamma rays emitted during nuclear decay.
Radiation Risk Relates to the risk that an exposure could lead to an adverse health effect in the individual exposed and/or result in heritable mutations that could lead to diseases in offspring.
Radioactivity The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
Radioisotope An unstable form of a chemical element that emits radiation as it breaks down and becomes more stable.
Radiology The science that investigates all forms of ionising radiation in the diagnosis and treatment of disease.
Radon A naturally occurring radioactive gas which emits alpha-particles.
Randomised Employs random selection or sampling in an experiment or procedure.
S Self-medication A behaviour in which a person uses a substance to self-treat a physical or psychological ailment.
Single strand break A type of DNA damage that involves breakage of only one DNA strand. This type of damage is easily repaired, although in some instances it could lead to the formation of a DNA mutation.
Stem cell An undifferentiated (not specialised) cell which can indefinitely produce other cells that continue as stem cells and other cells that become differentiated (specialised) such as a muscle cell, brain cell or a blood cell.
Stress Mental or emotional strain resulting from adverse circumstances.
Systematic Methodical, not random.
Systematic review A review that summarises the evidence on a clearly formulated review question according to a predefined protocol, using systematic and explicit methods to identify, select and appraise relevant studies, and to extract, analyse, collate and report their findings. It may or may not use statistical techniques, such as meta-analysis.
Systolic blood pressure The pressure in your blood vessels when the heart beats.
T Tumour A mass of tissue composed of abnormal or diseased cells. Tumours can be benign or malignant (cancerous).
V Vascular Dementia Another common form of dementia caused by impaired blood flow to the brain.
W Well-being Someone’s well-being is their health and happiness.
Whole Genome Sequencing (WGS) A laboratory process that is used to determine the sequence (or code) of nearly all of an individual’s complete DNA sequence.
Worry Bothersome thoughts about potential future events that make you feel unhappy or produce negative emotions.