X-chromosome
X chromosome is one of the two sex-determining chromosomes in many animal species, including mammals (the other is the Y chromosome). It is a part of the XY sex-determination system and X0 sex-determination system. The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for its similarity to the letter "Y".
Structure[edit | edit source]
The X chromosome in humans spans about 155 million base pairs (the building material of DNA). It represents approximately 5% of the total DNA in women's cells, containing about 2000 genes, compared to the Y chromosome containing just 78 genes.
Genetic disorders[edit | edit source]
Certain genetic disorders can be traced to the X chromosome. These are known as X-linked disorders. The most common is hemophilia, a disorder that affects the blood's ability to clot. Other X-linked disorders include Duchenne muscular dystrophy, Fragile X syndrome, and X-linked agammaglobulinemia.
Inheritance[edit | edit source]
In mammals, the X chromosome carries a larger number of genes than the Y chromosome. This means that any gene on the X chromosome can be present in two copies in females (XX) but only one copy in males (XY). This difference in gene dosage is compensated by X inactivation.
X inactivation[edit | edit source]
X inactivation is a process by which one of the two copies of the X chromosome present in female mammals is inactivated. The choice of which X chromosome will be inactivated is random in placental mammals.
See also[edit | edit source]
References[edit | edit source]
X-chromosome Resources | ||
---|---|---|
|
|
Translate to: East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
Urdu,
বাংলা,
తెలుగు,
தமிழ்,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
European
español,
Deutsch,
français,
русский,
português do Brasil,
Italian,
polski
Navigation: Wellness - Encyclopedia - Health topics - Disease Index - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD
WikiMD is not a substitute for professional medical advice. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD