Disease Glossary

Acid / base disturbances: A set of diseases where the pH of body fluids is either too low or too high. Disturbances are often a consequence of problems with lung or kidney function, and if untreated can lead to death.

Achondroplasia: A bone growth disorder which is the most common form of short limbed dwarfism.

Acute renal failure: The kidney plays an essential role in excreting toxins from the body. However, kidney function can fail, for example as a consequence of massive blood loss. This has effects on the heart and nervous system, and can be fatal.

Age-related Macular Disease (of the eye): Slow degeneration of the retinal epithelial pigment cells of the eye leading to loss of vision and eventual blindness.

Alzheimer disease: The most common cause of dementia. Associated with the development of plaques and neurofibrillary tangles in the brain, leading to memory loss and mood swings.

Aniridia: The congenital absence of the iris in the eye, caused by mutations in the PAX6 gene.

Apparent mineralocorticoid excess: In this inherited disease patients have high blood pressure caused by salt and water retention.

Asbestosis: Scarring of the lung. It is caused by inhalation of asbestosis fibres. Such fibres also increase the likely hood of developing lung cancer.

Ataxia: Patients with this disease have problems controlling their muscles, leading to problems walking, speaking and doing things we take for granted such as dialling a phone number. It is caused by mutations in genes that make K+ and Ca2+ channels found in nerves in the brain.

Bartter's syndrome: An inherited disease where inappropriate loss of salt and water in the urine leads to low blood pressure. Carriers of this disease (who show no symptoms otherwise) have been shown to have some protection against high blood pressure.

Basal cell carcinoma: A common form of skin cancer.

Bipolar disorders: Also known as manic depression. Patients demonstrate severe highs and lows, leading to cognitive and functional impairment.

Branchio-Oto-Renal syndrome: One of the more common causes of childhood deafness. Additional problems include renal disease. Caused by mutations in the EYA1 or SIX1 genes.

Cancer: Caused by problems with cell proliferation. There are more than 200 different types of cancer.

Charcot-Marie-Tooth disorder type 2: Main clinical symptoms in 90% of cases are early onset, symmetrical muscle weakness and wasting (predominantly in the distal lower limbs), foot deformities and walking difficulties associated with reduced or absent tendon reflexes.

Ciliopathies: a broad class of genetic disorders - that include Bardet-Biedl and Meckel and Joubert syndromes -  that affect the function of cilia and flagella in cells, and which result in a spectrum of problems including retinal blindness, obesity, renal failure (polycystic kidney disease), hydrocephalus and mental retardation.

Cleft lip and palate: About 1 in 800 live births in the UK show some degree of cleft defect. Clefts of the lip and/or palate occur early in development and can vary in severity from minor defects where parts of the embryonic processes forming the face and palate fail to fuse to very serious cosmetic defects where no fusion occurs that also cause problems with speech, swallowing and nutrition in affected babies.

Congenital absence of pain: The detection of pain is an important protective mechanism (think about how you react to heat) and nerves play a critical role in this process. A small number of families however, cannot feel pain due to inherited mutations in genes that are important in nerve function.

Craniosynostosis syndromes: Premature fusing of the skull bones leading to pronlems with brain and skull growth. Examples include Pfeiffer's, Crouzon's).

Cystic fibrosis: An inherited disease affecting 1 in 2500 individuals in the UK. Caused by problems with Cl- handling in epithelial cells. In the lungs this leads to an increased risk of infection and lung damage, which is fatal in 70% of sufferers.

Deafness (hearing loss): It is often argued that this is not a disease but it is an undesirable condition and considerable resources are spent by the NHS in terms of treatment and care. Most kinds of hearing loss are sensorineural, involving irreversible loss of the sensory hair cells and neurons in the inner ear. Hearing loss is largely an age-related condition afflicting more than 1 in 7 people in the UK and over 250 million worldwide

Dent's disease: Patients with this disease lose protein and phosphate in the urine, and as a consequence have a high risk of kidney failure. This inherited disease is caused by problems with a transport protein found in the renal proximal tubule.

DFNB1/Connexin 26 deafness: The most common form of inherited deafness.

Diabetes: a condition that affects around 3 million people in the UK.  It is characterized by reduced amounts of a hormone called insulin, or lack of ability to respond to insulin, which results in too much glucose in the blood.  It can be controlled by diet and sometimes by tablets or injections.

Diabetes insipidus: Patients with this disease excrete copious quantities of very dilute urine, as they have a problem with water handing in the kidney.

DiGeorge syndrome: A disorder involving congenital heart, thyroid and craniofacial defects, and later behavioural symptoms, such as an increased risk of schizophrenia.

Duchenne muscular dystrophy: Second commonest inherited disease affecting 1:3000 live male births. Leads to severe muscle wasting, loss of ambulation in teens and premature death, usually in the third decade.

Ectopic kidney: Where a kidney develops in the wrong place. Affects 1 in 800 individuals and increases the risk of kidney stone formation.

Emery-Dreifuss Muscular Dystrophy: Like other muscular dystrophies it is a wasting disease of muscle. It usually begins in childhood or adolescence. The features, which make it unique and different from other muscular dystrophies, are the early development of muscle contractures, the distribution of muscle weakness, and the fact that the heart may be affected in a particular way.

Epilepsy: A complex disease that affects around 1% of the population. Associated with inappropriate activity in the brain leading to epileptic seizures. Multiple causes, including gene mutations, brain damage and brain tumours.

Gitelman's syndrome: Another inherited renal disease leading to salt loss. Affects the distal tubule in the kidney.

Glioma: Cancer that originates in the brain or spinal cord.

Heart failure: Inefficient pumping of blood around the body by the heart as a consequence of damage to heart muscle. Often caused by myocardial infarction or hypertension, and may also be inherited. The lack of oxygenated blood leads to tiredness, breathlessness, nausea and dizziness.

HIV & AIDS: Human immunodeficiency virus (HIV) is a virus that attacks the immune system. It leads to the condition AIDS. Patients with AIDS are very vulnerable to opportunistic infections.

Holoprosencephaly: Failure of the forebrain to develop, leading to brain and facial defects. One of the most severe facial defects is cyclopia, the development of a single eye.

Horseshoe kidney: Fusing of the kidneys across the midline, which increases the risk of kidney stone formation. Affects 1 in 100 individuals.

Hutchinson-Gilford progeria syndrome: Progeria is a rare condition that is remarkable because its symptoms strongly resemble normal human aging, but occur in young children. Ninety percent of children with progeria have a mutation on the gene that encodes the protein lamin A. Inevitably, progeria is associated with a short lifespan with the average patient surviving to the early teens.

Hypertension: High blood pressure. This is not a single disease, but has many different causes, some inherited and some acquired. Many of the diseases listed in this glossary are associated with hypertension.

Infertility: a condition that affects around 1 in 6 couples in the world at sometime.  It is unusual as it affects a couple, not just an individual.  In essence this means that a couple cannot have a baby, but the reasons behind this can be very complicated.  Many types of infertility can be treated successfully by medical intervention such as IVF.

Inflammatory Bowel Disease (IBD): is a group of inflammatory conditions of the colon and small intestine. The major types of IBD are Crohn's disease and ulcerative colitis. Patients have a genetic predisposition that is exacerbated by environmental factors including gut microbes and stress.

Irritable Bowel Syndrome (IBS): is a common condition in which patients have pain associated with diarrhoea or constipation but without any obvious pathological features – it is therefore considered to be part of a group of conditions that are refereed to as functional pain syndromes.

Ischemic heart disease: Caused by the deposition of cholesterol plaques on the walls of coronary blood vessels, leading to vessel narrowing and a reduction in the blood supply to heart cells. This decreases the oxygen supply and can lead to cell death. Patients have a high risk of myocardial infarction and increased morbidity.

Liddle's syndrome: An inherited form of high blood pressure (hypertension) caused by salt retention by the kidneys.

Long QT syndrome: Can be inherited or acquired. A problem with the excitability of the heart leads to sudden death in affected individuals.

Malignant hyperthermia: In this rare inherited disease sufferers are sensitive to anaesthetics, responding with a massive rise in body temperature that must be controlled to prevent death. Many are unaware that they have the problem until they have an operation.

Mandibuloacral dysplasia: Main clinical symptoms are mandibular and clavicular underdevelopment, delayed closure of the cranial suture, joint contractures and abnormal distribution of adipose tissue.

Medulloblastoma: most common form of childhood brain tumour affecting 1 in 150,000 children with peak incidence at age 5. Affects the development and function of the brainstem structure called the cerebellum.

Meniere's disease: A disease of the inner ear associated with vertigo, tinnitus and hearing loss.

Myotonia: A rare inherited disease associated with hyperexcitable skeletal muscles, which contract inappropriately. Patients suffer from stiff muscles and also have myotonic seizures.

Parkinson Disease: The second most common neurodegenerative disorder. Caused by progressive loss of nerves in the central brain leading to tremors, slow, stiff movements, and other symptoms.

Paroxysmal extreme pain disorder: also called "Man on fire syndrome" is caused by a mutation in sodium channel called NaV1.7 leading to excessive signalling in pain pathways. The opposite is a mutation that cause congenital insensitivity to pain.

Pendred's syndrome: Causes 10% of cases of sensorineural deafness, with patients demonstrating goitre (enlargement of thyroid gland).

Polycystic kidney disease: The most common inherited kidney disease. Associated with long term replacement of normal kidney tissue with fluid filled cysts. 50% of sufferers require dialysis or a kidney transplant.

Polysyndactyly: a rare development disorder. Patients have additional and webbed toes, and heart defects.

Prostate cancer: Second most common male malignancy in the western world with 1 in 6 men likely to be affected at some point in their lifetime.

Pseudohypoaldosteronism: Problems with salt and water handing in this disease lead to low blood pressure and frequent lung problems. Patients often have a permanent "runny" nose!

Renal distal tubule acidosis: In this inherited disease patients excrete too much bicarbonate in the urine, leading to a fall in body fluid pH (known as an acidosis).

Retinal degeneration: A group of diseases associated with the gradual loss of the retina and therefore sight in the individual. Can be acquired (e.g. caused by blood supply problems) or inherited.

Schizophrenia: A personality disorder that affects approximately 1% of adults. Associated with susceptibility genes and environmental factors. Symptoms include mood swings and cognitive impairments.

Startle disease: In this disease patients have an exaggerated startle response (i.e. if they get a shock they jump higher and flail their arms about more). The cause is a lack of function in inhibitory nerves in the brain.

Stroke: The 3rd most common cause of death. A consequence of a clot blocking a blood vessel (ischemic stroke) or a burst blood vessel (haemorrhagic stroke) in the brain leading to cell damage and death. Symptoms vary depending on the area of the brain where the damage occurs.

Timothy syndrome: This devastating disease is associated with autism, cardiac arrhythmias and developmental abnormalities. It is caused by mutations in the gene that makes a particular type of Ca2+ channel.

Tinnitus: Noises generated in the auditory central nervous system in the absence of sound. Most people experience this condition transiently but for many it is persistent and causes substantial distress.