Gelineau syndrome: A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Named for a French neurologist, JBE Gelineau (1859-1906). Also known as narcolepsy.
The disorder is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary muscles associated with a strong emotion), sleep paralysis (immobility of the body that occurs in the transition from sleep to wakefulness), what are called hypnagogic hallucinations (pre-sleep dreams) and automatic behaviors (such as doing something “automatically” and not remembering afterwards how one did it).
125,000 Americans are estimated to have narcolepsy. It strikes males and females and all races. Symptoms most commonly appear in a person’s teens and early twenties. The disease can vary in severity. Some persons with it have mild sleepiness or rare cataplexy (less than one episode per week). Other persons may have moderate sleepiness or infrequent cataplexy (less than one episode a day). Still other persons with narcolepsy may experience severe sleepiness or have severe cataplexy (with one or more episodes of cataplexy per day).
The cause(s) of narcolepsy are unknown. It is not a fatal disorder in itself but it can lead to fatalities. For example, a narcoleptic may fall asleep while driving.
Narcolepsy is usually treated with a medication to improve alertness and an anti-depressant that helps control cataplexy. The U.S. Food and Drug Administration (FDA) in 1998 approved Provigil (modafinil), a non-amphetamine drug for treating the excessive sleepiness of narcolepsy.
Other names for this disorder include excessive daytime sleepiness (EDS), hypnolepsy, sleeping disease, and paroxysmal sleep.
Gene: The basic biological unit of heredity. A segment of deoxyribonucleic acid (DNA) needed to contribute to a function. An official definition: According to the official Guidelines for Human Gene Nomenclature, a gene is defined as “a DNA segment that contributes to phenotype/function. In the absence of demonstrated function a gene may be characterized by […]
- Gene amplification
Gene amplification: Making multiple copies of a gene. Repeated copying of a gene. Gene amplification plays a role in cancer cells. A tumor cell amplifies, or copies, DNA segments as a result of cell signals and sometimes environmental events. Amplification can occur in vivo (in the living individual) or in vitro (literally “in glass”, or […]
- Gene array analysis
Gene array analysis: A way of analyzing the differential expression of thousands of species of mRNA (messenger RNA) at the same time in two different samples (as, for example, in normal vs. tumor tissue, or at different developmental stages). Gene array analysis involves synthesizing labeled cDNA (complementary DNA) from 2 or more sources, and hybridizing […]
- Gene deletion
Gene deletion: The total loss or absence of a gene. Gene deletion plays a role in birth defects and in the development of cancer.
- Gene duplication
Gene duplication: An extra copy of a gene. Gene duplication is a key mechanism in evolution. After a gene is duplicated, the once-identical genes can undergo changes and diverge to create two different genes.