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

Areflexia

The absence of reflexes.

Source: 

Areflexia. (n.d.). Retrieved June 27, 2019, from link.

Ataxia

The difficulty with or loss of muscle coordination and bodily movements.

Source: 

What is ataxia? (n.d.). Retrieved June 27, 2019, link.

Autosomal

Inheritance characteristic where a gene is located on a numbered, non-sex chromosome. These are found on one of the 22 pairs of (44 total) autosomal chromosomes in a human body where DNA is stored. This is one of several ways that a trait, disorder, or disease can be passed down through families. These chromosomes are not the sex (X or Y) chromosomes.

Source: 

Shiel, W. C. (2018, December 11). Definition of Autosomal. Retrieved June 6, 2019, from link.

Autosome

Any chromosome in a cell that is not an X or Y sex chromosome. The average person has 22 pairs of autosomes (44 autosomes in total) in each cell that define the genetic make-up, or DNA, of the being. These chromosomes store thousands of genes and they are inherited from the beings’ parents. In addition to the 22 pairs of autosomes (44 total), beings also have one pair (2 total) sex chromosomes (X and Y in a male, and X and X in a female).

Source: 

Shiel, W. C. (2018, December 4). Definition of Autosome. Retrieved June 6, 2019, from link.

Shiel, W. C. (2018, December 11). Definition of Autosomal. Retrieved June 6, 2019, from link.

Autosome – Definition and Function of Autosomes. (2017, April 28). Retrieved June 7, 2019, from link.

Axon

Long and single nerve-cell process that usually conducts impulses away from the cell body.

Source: 

Axon. (n.d.). Retrieved June 27, 2019, from link.

B

Batten disease

Batten disease is the common name for a broad class of rare, inherited disorders or diseases of the nervous system also known as neuronal ceroid lipofuscinoses, or NCLs. In these diseases, a defect in a specific gene triggers a cascade of problems that interferes with a cell’s ability to recycle certain molecules. The disease has several forms that share some of the same features and symptoms but vary in severity and age when symptoms first begin to appear. Each form is caused by a variant in a different gene. Although “Batten disease” originally referred specifically to the juvenile-onset form of NCL, the term Batten disease is increasingly used to describe all forms of NCL. The disease ultimately leads to shortened lifespan.

Source: 

Batten Disease Fact Sheet. (2019, June 24). Retrieved July 31, 2019, from link.

Benign variant

When a variant has no impact on health and is recognized as a neutral variant.

Source: 

What is a variant? (n.d.). Retrieved July 1, 2019, from link.

C

Clinical trial

A study conducted in humans that evaluates the effectiveness, safety, and side effects of investigational products (which could include medications, treatments, and devices) that have the possibility of treating a disease in that particular patient group.

Source: 

Clinical trials. (n.d.). Retrieved December 5, 2019, from link.

Contractures

Tightening in or around a joint that occurs when muscles surrounding the joint weaken and other muscles remain strong or increase in strength to accommodate the weakness. Joint contractures are more common in the feet, ankles, hips, hands, and wrists.

D

Degradation

The erosion of a molecule.

Source: 

Polymer degradation. (n.d.). Retrieved December 5, 2019, from link.

Dementia

The loss of cognitive functioning which includes thinking, remembering, and reasoning which result in behavioral issues that interfere with an individual’s daily life.

Source: 

What Is Dementia? Symptoms, Types, and Diagnosis (n.d.). Retrieved August 16, 2019, from link.

Demographics

Statistical characteristics of a human population (for example, age or income) to help identify markets or segments.

Source: 

Demographic. (n.d.). Retrieved June 5, 2019, from link.

Demyelinating neuropathy

Refers to the loss or damage to the myelin or protective covering of the nerve tissue. This damage leads to slowed nerve impulses, causing neurological problems.

Source: 

Demyelinating disease: What can you do about it? (n.d.). Mayo Clinic. Retrieved July 1, 2019, from link.

Developmental regression

When a child loses an acquired function, milestone or fails to progress beyond a prolonged plateau after a period of relatively normal development.

Source: 

Developmental regression. (n.d.). Retrieved August 16, 2019, from link.

Distal muscles

Muscles that are farther away from the torso (forearms, calves, feet, hands).

Source: 

Source: Distal Myopathy. (n.d.). Retrieved December 5, 2019, from link.

E

Endoplasmic reticulum (ER)

A continuous membrane system that forms a series of flattened sacs within the cytoplasm of eukaryotic cells and serves multiple functions, but most importantly the transport of proteins through the body.

Source: 

Rogers, K. (2018, August 24). Endoplasmic reticulum. Retrieved June 26, 2019, from link.

Enzyme

A protein responsible for speeding the rate of chemical reaction in the cell of the living organism. Enzymes support a wide range of functions in an organism, as they spark chemical reactions. Enzymes work with, or interact with, substrates (the underlying surface or substance). When reacted together, the enzyme and substrate result in a new product or molecule that then separates from the original enzyme and goes on to create new reactions in the cell.

Source: 

Enzyme substrate complex. (n.d.). Retrieved June 5, 2019, from link.

Castro, J. (2014, April 26). How Do Enzymes Work? Retrieved June 5, 2019, from link.

Expanded exome sequencing panel

Through this diagnostic test performed by a geneticist, the exome — a sequence of all exons of protein coding genes in the human genome — can be captured and analyzed with the intention of identifying a disease with a genetic component.

Source: 

Warr, A., Robert, C., Hume, D., Archibald, A., Deeb, N., & Watson, M. (2015, Aug.). Exome Sequencing: Current and Future Perspectives, G3, 5(8), 1543-1550. Retrieved December 6, 2019, from link.

New England Primate Research Center. (2011, Sept.) Expanding whole exome resequencing into non-human primates, Genome Biology, 12(9). Retrieved December 6, 2019, from link.

G

Genetic disease

A disorder in a person’s structural and functional state that is caused by a change, or variant, in an individual’s DNA sequence. This variant may or may not be hereditary.

Source: 

What is a genetic disorder? (2014). Retrieved June 5, 2019, from link.

Glycoprotein

A molecule made up of a carbohydrate and a protein that plays an essential role in the body, particularly in the body’s immune responses.

Source: 

Glycoprotein. (n.d.). Retrieved June 5, 2019, from link.

Glycosylamine

A type of glycoside. A biochemical compound having a glycosyl group attached to an amino group. They are also known as N-glycosides.

Source: 

Moss, G., Smith, P., & Tavernier, D. (2009). Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995). Pure and Applied Chemistry, 67(8-9), 1307-1375. Retrieved July 1, 2019, from link.

Gross motor functions

The ability to make large, general movements, such as waving an arm or lifting a leg. This requires proper coordination and function of muscle, bones, and nerves.

 

Source: 

Gross motor control. (n.d.). Retrieved August 14, 2019, from link.

H

Hallucination

The perception of something that in reality does not exist.

Source: 

Teeple, R., Caplan, J., & Stern, T. (2009). Visual Hallucinations: Differential Diagnosis and Treatment, Primary Care Companion Journal of Clinical Psychiatry, 11(1), 26-32. Retrieved August 16, 2019, from link.

Hyperactivity

A condition of being overly active.

Source: 

Hyperactivity. (n.d.). Retrieved August 16, 2019, from link.

I

Incidence

The rate of new (or newly diagnosed) cases of a disease.

Source: 

Incidence. (n.d.). Retrieved on December 5, 2019, from link.

J

Joint laxity

Refers to the looseness and instability of a joint. This looseness results in the tissues holding the joints together having hypermobility and may allow an individual to extend them easily and painlessly beyond the normal range of motion.

Source: 

Gabbey, A. E. (2017, April 24). Hypermobile Joints: Causes, Treatments, and Relief. Retrieved June 26, 2019, from link.

L

Later onset of disease

When signs and symptoms of a disease display later in life.

Likely pathogenic variant

A variant that was previously unreported but is likely expected to cause disease.

Source: 

What is a variant? (n.d.). Retrieved July 1, 2019, from link.

Lysosomal storage disorders

Inherited metabolic diseases that are characterized by an abnormal build-up of waste products in the body’s lysosomes caused by enzyme deficiencies. Nearly 50 of these disorders have been discovered, two of which are CLN7 and CLN5, and these diseases lead to progressive physical and mental deterioration.

Source: 

Lysosomal Storage Disorders. (2006). Retrieved June 5, 2019, from link.

Greiner-Tollersrud, O. K., & Berg, T. (2013). Lysosomal storage disorders. Retrieved June 5, 2019, from link.

Lysosomal Diseases New Zealand. (n.d.). Retrieved June 5, 2019, from link.

Lysosomes

Specialized vesicles within cells that digest large molecules, breaking down excess waste products of the cell with the help of enzymes. Lysosomes may also be used to destroy invading viruses and bacteria.

Source: 

Lysosomal Storage Disorders. (2006). Retrieved June 5, 2019 from link.

Greiner-Tollersrud, O. K., & Berg, T. (2013). Lysosomal storage disorders. Retrieved June 5, 2019, from link.

Lysosomal Diseases New Zealand. (n.d.). Retrieved June 5, 2019, from link.

M

Masgutova Neuro-sensory-motor Reflex Integration (MNRI)

A type of therapy invented by Dr. Masgutova that uses reflex patterns to awake an individual’s sensory-motor memory in order to self-restore impaired functions such as ability to walk, see, hear, remember, and regulate emotion.

Source: 

What is the Masgutova Method®/MNRI?. (2019). Retrieved August 22, 2019, from link.

Mutation

A mutation is any inherited genetic change. The term “mutation” is being replaced by the term “variant.”

Source: 

Mutation (n.d.). Retrieved September 13, 2019, from link.

Myelin

A soft white material that forms a thick layer around the axons of some neurons and is composed chiefly of lipids (such as cerebroside and cholesterol), water, and smaller amounts of protein.

Source: 

Myelin. (n.d.). Retrieved June 26, 2019, from link.

Myoclonic epilepsy or jerks

Brief, shock-like jerks or twitching of a muscle (myoclonus).

Source: 

Myoclonic seizures. (n.d.). Retrieved June 26, 2019, from link.

N

Natural history study (non-interventional study)

There are two types of natural history studies: prospective and retrospective. A natural history study examines a group of people who have a specific medical condition or disease or are at risk of developing one. A natural history is non-interventional and collects health information in order to understand how the medical condition or disease develops and how to possibly treat it. No treatment or investigational product is given. In a prospective study, this data collection is forward-looking and is done over time in the future. In a retrospective study, researchers review and examine factors related to an outcome in the past by looking back on past exposures and medical events.

Source: 

NCI Dictionary of Cancer Terms. (n.d.). Retrieved June 5, 2019, from link.

Pariser, A. R. Importance of natural history studies in rare diseases [PowerPoint slides]. Retrieved June 5, 2019, from link.

Neuron

A nerve cell that receives and sends electrical signals from sensory cells and other neurons over long distances within the body. These signals are sent to muscle neurons and other neurons.

Source: 

Shiel, W. C. (2018, December 27). Definition of Neuron. Retrieved June 26, 2019, from link.

Neuronal ceroid lipofuscinosis (NCL)

Refers to a group of conditions that affect the nervous system. Signs and symptoms vary widely between the forms but generally include a combination of dementia, vision loss, and epilepsy.

Source: 

Neuronal ceroid lipofuscinosis. (n.d.). Retrieved June 26, 2019, from link.

Neuropathy

Nerve problem that causes pain, numbness, tingling, swelling, or muscle weakness in various parts of the body typically beginning in the hands or feet, then getting worse over time.

Source: 

Neuropathy. (n.d.). Retrieved June 26, 2019, from link.

Nucleus

A structure in most cells separated from the rest of the body. It controls and regulates the activities of the cell and carries genes.

Source: 

Nucleus. (2019, March 1). Retrieved June 26, 2019, from link.

Nystagmus

Involuntary and rapid eye movements, typically from side to side.

Source: 

Nystagmus American Optometric Association. (n.d.). Retrieved August 16, 2019 from link.

P

Pathogenic variant

A change in DNA that causes disease.

Source: 

What is a variant? (n.d.). Retrieved July 1, 2019, from link.

Peripheral neuropathy

Refers to conditions that result when nerves that carry messages to and from the brain and spinal cord from and to the rest of the body are damaged.

Source: 

Peripheral neuropathy. (n.d.). Retrieved December 5, 2019, from link.

Peroneal muscles

A group of muscles in the leg.

Source: 

Peroneus. (n.d.). Retrieved December 5, 2019, from link.

Prevalence

The total number of individuals in a population who have a disease or health condition at a specific period of time, usually expressed as a percentage of the population.

Source: 

Prevalence. (n.d.). Retrieved December 5, 2019, from link.

Proprioception

The unconscious awareness of sensations coming from one’s joints, muscles, tendons, and ligaments.

Source: 

Proprioception. (n.d.). Retrieved August 22, 2019, from link.

Prospective study

A natural history study that reviews subjects over a forward-looking length of time to observe for outcomes in the development of a disease.

Source: 

Prospective. (n.d.) Retrieved December 5, 2019, from link.

Proximal muscles

Muscles that are located closer to the torso (neck, shoulder, biceps).

Source: 

Proximal. (n.d.). Retrieved December 5, 2019, from link.

R

Retinitis pigmentosa

A group of eye diseases that lead to eventual progressive vision loss.

Source: 

Retinitis pigmentosa. (n.d.). Retrieved April 24, 2019, from link.

Retrospective study

A natural history study that reviews and examines factors related to an outcome in the past by looking back on past exposures and medical events.

S

Sensory neuropathy

Refers to nerves that provide feeling.

Source: 

Neuropathy. (n.d.). Retrieved December 5, 2019, from link.

T

Tendon reflexes

A tendon is a tough cord or band of dense white fibrosis connective tissue that unites a muscle with another part (for example a bone) and exerts a reflex action in which a muscle is made to contract by a blow upon its tendon.

Source: 

Tendon reflex. (n.d.). Retrieved June 1, 2019, from link.

U

Uncertain significance

A gene variant that is previously unreported and is of the type which may or may not be causative of the disorder.

Source: 

What is a variant? (n.d.). Retrieved July 1, 2019, from link.

V

Variant

A variant is a change in DNA. A variant may or may not cause disease. The following modifiers describe the variant: (i) pathogenic, (ii) likely pathogenic, (iii) uncertain significance, (iv) likely benign, or (v) benign depending on whether or not the variant causes disease. For example, a “pathogenic variant” may cause disease. The term “variant” has replaced the term “mutation.”

Source: 

Richards, S., Aziz, N., Bale, S., Bick, D., Das, S., Gastier-Foster, J., Grody, W. W., Hegde, M., Lyon, E., Spector, E., Voelkerding, K., Rehm, H. L. (2015, May). Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genetics in Medicine. 17(5), 405-24. Retrieved September 12, 2019, from link.