ScienceIQ.com: Cool science facts delivered daily to your email


 Facts By Category:


 » Physics
 » Astronomy
 » Chemistry
 » Biology
 » Mathematics
 » Geology
 » Engineering
 » Medicine
 » Science

  by keyword search:

    
 ScienceIQ Team:


 »Writers & Editors



xUmp.com
Science Supplies,
Toys & Gifts

PhysLink.com
Physics & Astronomy
Online
Malaria and Sickle Cell Anemia


Sickle cell anemia is a genetic disorder in which the red blood cells collapse into a 'sickle' shape and cannot carry oxygen very well. They also tend to get stuck in narrow blood vessels, causing painful crises. The disease is caused by a change in one amino acid making up the large hemoglobin molecule that gives blood its red color and its oxygen carrying capacity. People who carry two copies of the defective gene (homozygotes) have only abnormal hemoglobin. This is a life-threatening disorder, and patients often die young.

People who have only one defective copy of the gene (heterozygotes) have enough normal hemoglobin to lead normal lives, and interestingly, they are somewhat resistant to malaria. The parasite that causes malaria lives part of its life cycle in red blood cells. It cannot live as well in blood cells that contain some abnormal hemoglobin.

Thus in places like Africa, where malaria is common, the gene for sickle cell anemia is much more common than it is among people in northern Europe. Even though having two copies makes people very sick, having one copy gives them an advantage if malaria is a threat. In the United States, sickle cell anemia is much more common among African-Americans than among Americans of European or Asian descent.

135

About the Author


Sandy BeckerSandy Becker, MA
Sandy Becker received a BA in history from Pomona College. She then earned two MAs in Biology, and now has 25 years of experience in developmental biology research, working with mouse embryonic stem cells. Sandy began writing science articles about ten years ago to share her knowledge of science. She is currently studying for her third MA, in science journalism.
Homepage of Sandy Becker

Further Reading
Malaria, West Nile, and Other Mosquito-Borne Diseases (Diseases and People)
by Nancy Day


Related Web Links
Genes and Disease
by NCBI

How Does Sickle Cell Cause Disease?
by Joint Center for Sickle Cell and Thalassemic Disorders





Home | Privacy Policy

Copyright © 2002-2017 ScienceIQ.com - All Rights Reserved