Diseases and Definitions

Amyotrophic lateral sclerosis – Amyotrophic lateral sclerosis, or ALS, is a disease of the nerve cells in the brain and spinal cord that control voluntary muscle movement. 
ALS is also known as Lou Gehrig's disease. 

Parkinson’s Disease – Parkinson's disease (PD) belongs to a group of conditions called motor system disorders, which are the result of the loss of dopamine-producing brain cells. The four primary symptoms of PD are tremor, or trembling in hands, arms, legs, jaw, and face; rigidity, or stiffness of the limbs and trunk; bradykinesia, or slowness of movement; and postural instability, or impaired balance and coordination. As these symptoms become more pronounced, patients may have difficulty walking, talking, or completing other simple tasks. PD usually affects people over the age of 50.http://www.ninds.nih.gov/disorders/parkinsons_disease/parkinsons_disease.htm 

Alzheimer’s Disease – Alzheimer's is a type of dementia that causes problems with memory, thinking and behavior. Symptoms usually develop slowly and get worse over time, becoming severe enough to interfere with daily tasks. http://www.alz.org/alzheimers_disease_what_is_alzheimers.asp 

Huntington’s Disease – Huntington's disease (HD) results from genetically programmed degeneration of brain cells, called neurons, in certain areas of the brain. This degeneration causes uncontrolled movements, loss of intellectual faculties, and emotional disturbance. HD is a familial disease, passed from parent to child through a mutation in the normal gene. Each child of an HD parent has a 50-50 chance of inheriting the HD gene.http://www.ninds.nih.gov/disorders/huntington/huntington.htm 

Charcot-Marie-Tooth Disease - Charcot-Marie-Tooth disease is a group of inherited disorders that affect the peripheral nerves (those outside the brain and spine). Charcot-Marie-Tooth is one of the most common inherited nerve-related disorders. Defects in at least 14 genes cause different forms of this disease. http://www.ninds.nih.gov/disorders/charcot_marie_tooth/detail_charcot_marie_tooth.htm

Traumatic Brain injury – Traumatic brain injury (TBI), a form of acquired brain injury, occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently hits an object, or when an object pierces the skull and enters brain tissue.http://www.ninds.nih.gov/disorders/tbi/tbi.htm 

Peripheral neuropathy – Peripheral nerves carry information to and from the brain. They also carry signals to and from the spinal cord to the rest of the body. Peripheral neuropathy means these nerves don't work properly. Peripheral neuropathy may be damage to a single nerve. It may be damage to a nerve group. It may also affect nerves in the whole body. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001619/ 

Familial disease – A familial disease is hereditary, passed on from one generation to the next. It resides in a genetic mutation that is transmitted by mother or father (or both) through the gametes to their offspring. 

Sporadic disease – occurring singly and haphazardly; widely scattered 

Mutation – A gene mutation is a permanent change in the DNA sequence that makes up a gene. Mutations range in size from a single DNA building block (DNA base) to a large segment of a chromosome. Although many polymorphisms have no negative effects on a person’s health, some of these variations may influence the risk of developing certain disorders. 

Genome-wide association study – A genome-wide association study is an approach that involves rapidly scanning markers across the complete sets of DNA, or genomes, of many people to find genetic variations associated with a particular disease. Once new genetic associations are identified, researchers can use the information to develop better strategies to detect, treat and prevent the disease. Such studies are particularly useful in finding genetic variations that contribute to common, complex diseases, such as asthma, cancer, diabetes, heart disease and mental illnesses. 

Cell Death (apoptosis) – A form of cell death in which a programmed sequence of events leads to the elimination of cells without releasing harmful substances into the surrounding area. Apoptosis plays a crucial role in developing and maintaining health by eliminating old cells, unnecessary cells, and unhealthy cells. 

Neurodegeneration – Neurodegeneration is the umbrella term for the progressive loss of structure or function of neurons, including death of neurons. Many neurodegenerative diseases including Parkinson’s, Alzheimer’s, and Huntington’s occur as a result of neurodegenerative processes. 

Nucleus – The nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins to form chromosomes. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression — the nucleus is, therefore, the control center of the cell. 

Axon – An axon is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma. Axons make contact with other cells—usually other neurons but sometimes muscle or gland cells—at junctions called synapses. 

Dendrite – Dendrites are the branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. Electrical stimulation is transmitted onto dendrites by upstream neurons via synapses which are located at various points throughout the dendritic arbor 

Synapse – A synapse is a junction that permits a neuron to pass an electrical or chemical signal to another cell (neural or otherwise). Synapses are essential to neuronal function: neurons are cells that are specialized to pass signals to individual target cells, and synapses are the means by which they do so