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

Autosomal Dominant: The human genome has 22 pairs of regular chromosomes called autosomes and one pair of sex chromosomes. An autosomal dominant disease describes a disorder in which the disease is expressed in those who have inherited only one mutated copy of a particular gene (heterozygotes) located in one of the 22 pairs of autosomes.

Autosomal Recessive: Describes a trait or disorder requiring the presence of a mutation in both copies of the gene at a particular locus in order to express observable disease; specifically refers to genes on one of the 22 pairs of autosomes (non-sex chromosomes).

C

Cerebellum: The cerebellum (Latin for little brain) is a region of the brain that plays an important role in the integration of sensory perception, coordination and motor control.

D

Degenerative disease: A degenerative disease is a disease in which the function or structure of the affected tissues or organs will progressively deteriorate over time, whether due to normal bodily wear or lifestyle choices such as exercise or eating habits or from a variety of disease causing mechanisms including abnormal genes

Degenerative diseases can be contrasted with other types of diseases such as infectious diseases, diseases due to external injury or diseases due to blood vessel occlusions such as strokes and heart attacks.

DNA: Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. The main role of DNA molecules is the long-term storage of genetic information.

G

Gene: A gene is the basic unit of heredity in a living organism. All living things depend on genes. Genes hold the information to build and maintain an organism's cells and pass genetic traits to offspring.

Genetics: The science of genes and heredity.

Genotype: The genotype is the sum total of genes transmitted from parent to offspring.

H

Hereditary disease: a disease or disorder that is inherited genetically.

M

Mitochondrial DNA: Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within cells that convert the energy from food into a form that cells can use

Multiple Sclerosis: Multiple sclerosis is an autoimmune disease that affects the brain and spinal cord (central nervous system). Symptoms vary, because the
location and severity of each attack can be different.

S

Spinal cord: The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends downward from the brain. The brain and spinal cord together make up the central nervous system.

Stroke: A stroke is the rapidly developing loss of brain function(s) due to disturbance in the blood supply to the brain.

T

Tumor: A tumor is an abnormal growth of body tissue. Tumors can be cancerous
(malignant) or non-cancerous (benign). Symptoms depend on the type
and location of the tumor.

X

X-Linked: X-linked genes are those that are located on the X chromosome. Females carry 2 x chromosomes and males carry one X and one Y chromosome.. A disease related to a mutation in a gene on the X chromosome is called X-linked. In X-linked recessive diseases, females carry the mutation but do not exhibit the disease because they also carry an X chromosome with a normal copy of the gene. Their male offspring who inherit the X chromosome with the mutated gene will exhibit the disease.