The differences in the Ryan and Paszty models may actually help researchers to test drugs, treatments and cures on two different systems. This development has been hailed as a breaking point for many researchers who wish to test new drugs aimed at initiating HbF production after birth to take advantage of its anti-sickling affects. Others in the field wish to test their "anti-clumping" drugs on these new mice. Though the old mouse models showed some symptoms of sickle cell anemia the Paszty and Ryan models are better because their HbS globin is human and the exact mutant and they show the symptoms more naturally than the other mouse models. (Barinaga, 1997)

Along with the transgenic mice other advances in research of sickle cell anemia have been made. At Duke University a new type of therapy is on the horizon, which would use the difference in mRNA’s of the HbA and the HbS to eliminate the HbS from the blood stream using ribozymes. They propose that if "10 to 20%" of the HbS mRNA could be corrected it would be worth it to the patients. The ribozymes would splice a new portion of the correct sequence into the HbS mRNA’s to create a new mRNA that would function like HbA mRNA by producing the same protein rather than the mutant HbS protein. Further hope in this therapy is to insert these ribozymes into the stem cells that make the red blood cells and fix the problem at the source, thus giving a continuous "good" source of hemoglobin. (George, 1998)

On December 11, 1998 world history was made twice, first with the first unrelated stem cell transplant at Egelston Children’s Hospital in Atlanta, and the possibility of being "cured" of sickle cell anemia. This big leap is one that may give hope to millions of people. After this momentous event five other children have undergone a similar transplant with their siblings’ stem cells to have the same results. (Eckman, MD, 1999)

Although very encouraging for some this "cure" will not be available to the entire human population soon because of the complexity and the amount of money which is part of the cure. This means that other sickle cell treatments and cures must still be found that are ideally as cost effective as immunizations and just as easy so that these cures can be brought to other less populated and more isolated areas. Hopefully in the decades to come the sickle cell research will grow with leaps and bounds similar to the way it has in this decade.

Bossed skull-A square shaped skull linked with sickle cell anemia

DNase I super-hypersensitive Sites- The site found up stream of the human hemoglobin proteins which must be placed in front of the human hemoglobin proteins for
    increased hemoglobin yeld in mice

Human genetic diseases- A human genetic disease is the influence of mutant genetic alleles on a human to produce unwanted genetic traits (such as the sickling of sickle
    cells)

Genetic tools- Tools such as restriction enzymes and other protocols that allow scientists to manipulate dna

Hemoglobin-  Alpha and beta hemoglobin are proteins that pick up oxygen and carry it in the red blood cell to other parts of the body from the lung.  gamma hemoglobin
    is the fetal form (Click here for an educational link)(John, 1999)

Igbo tribe- An African tribe located in Nigeria

Linus Pauling - A theorist involved in the discovery of sickle cell anemia, he has won the noble prize twice

Locus Control Regions- See DNase I super-hypersensitive sites

Malaria-  A disease carried by mosquitos and prevalent in marshy swamplands in third world countries and rural areas

"obanje"-"the children who come and go" or children who are thought to be similar to their previous brothers and sisters that have died and so are thought to be that
    "spirit" come back to haunt the parents with bad luck

Sickle cell anemia-The disease caused by the human hemoglobin sickle allele, also known as sickle cell disease

Sickle cell trait- The name given the condition a person has if they have only one sickle cell allele

Transgenic- To have the genes of another organism or another allele that is not normaly a part of the orginal organism ( usually inserted or bred into the organism).
 

Barinaga, Marcia.  Mutant Mice Mimic Human Sickle Cell Anemia.  Science:278; 1997 p 803-804.

Carlson, Elof Axel.  Human Genetics.  D. C. Health and Company, 1984.

Eckman, J. MD and Allan Platt PA-C.  Sickle Cell Research: Web Update. The Sickle Cell Information Center.
    http://www.cc.emory.edu/PEDS/SICKLE/Reserch.htm

Edelstein, Stuart J.  The Sickled Cell: From Myths to Molecules.  Harvard University Press, 1986.

George, Karyn Hede.  Duke Researchers Call Gene Therapy A Promising Strategy for Sickle Cell Anemia.  The Sickle Cell Information Center.
    http://www.cc.emory.edu/PEDS/SICKLE/serv04.htm#geneTherapy

John. Introduction to Blood.  Univiersity of Washington Health Sciences Center for Educational Resources. http://cer.hs.washington.edu/John/

Johnson, Mohamed Ismail M.P.H.  The World and the Sickle Cell Gene: A Study in Health Education.  Trado-medic Books, 1984.

Linde, Shirley Motter MS.  Sickle Cell: A complete guide to prevention and treatment. Pavilion Publishing Company, 1972.

Ryan et al.. Human Sickle Cell Hemoglobin in Transgenic Mice.  Science:247; 1990 p 566-568.

Ryan et al..  Knockout-Transgenic Mouse Model of Sickle Cell Disease. Science: 278; 1997 p 873-876.

Paszty et al.. Transgenic Knockout Mice with Exclusively Human Sickle Hemoglobin and Sickle Cell Disease. Science: 278; 1997 p 876-878.
 

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