Transcript Slide 1
Changes in the F8 gene are responsible for hemophilia A while mutations in the F9 gene cause hemophilia B The F8 and F9 gene provides instructions for producing the coagulation factor VIII a protein that helps with blood clotting. Mutations in the F8 or F9 gene lead to the production of an abnormal version of coagulation factor VIII or coagulation factor IX, or reduce the amount of coagulation. Definition of coagulation: to thicken, or cause liquid to thicken, into a soft semisolid mass Hemophilia A is caused by a deficiency of factor VIII and hemophilia B is caused by a deficiency in factor IX. Factor VIII and IX play essential roles in the blood Coagulation system. physical symptoms •Large bruises •Bleeding of the mouth and gums, tooth loss •Blood in the urine •Digestive problems •Nosebleeds •Joint pain and swelling, frequently in the knees and elbows •Heavy bleeding, or bleeding that lasts a long time, from an accident or other injury •Swelling under the skin and between muscles, with fever, skin discoloration, and pain This condition occurs more commonly in males. Hemophilia A is the most common type of the condition. One in five thousand males worldwide are born with this disorder. Hemophilia B occurs in approximately 1 in 20,000 newborn males worldwide. Hemophilia is the most common X-linked genetic disease. Hemophilia is linked in the X chromosome. Normal genotypes are XY, but in an affected human the genotype would be X and Xh. This is the extra chromosome that causes the hemophilia. Hemophilia is passed down from mother to son and is extremely rare for a woman to have hemophilia. Women must be a carrier of the disorder for her son to get it. Females have two X chromosomes and males only have one. When a boy is born, he takes one X chromosome from his mother and one Y chromosome from his father. Therefore, he can only get hemophilia through his mother. If there is a mother that is a carrier and has a daughter the gene could be passed down to her, but it is very possible she would only be a carrier and have no symptoms. Example One: Mother(Carrier)+Father(NonAffected)=50% chance of their son acquiring the disorder and 50% chance of their daughter being a carrier. Example Two: Mother(Not Affected)+Father(Hemophiliac)=All sons will be non-affected and all daughters will be carriers The two female offspring are heterozygous for the hemophilia trait and are carriers. The two male offspring receive an unharmed X-chromosome and are regular. There is a male and female offspring that inherit regular genes. One female is heterozygous for hemophilia and is a carrier. One male gets a damaged Xchromosome and will have hemophilia. Hemophilia is treated by replacing the missing clotting factor in the blood. Concentrates of clotting factor VIII (for hemophilia A) or clotting factor IX (for hemophilia B) are either dripped or injected in the vein. This helps to replace the clotting factors that are either missing or low. Clotting factors: •factor concentrates •cryoprecipitate •plasma •whole blood Nearly all research is being focused on gene therapy treatment. Hemophilia gene therapy research is trying to replace the defective gene with a working functional gene. So far there have not been any accepted gene therapy treatments but researchers have found success of the gene therapy treatment in mice. Depending on the severity of a person hemophilia there quality of life changes. A person with mild hemophilia everyday life is not that different than a normal person's life. Although many precautions need to be taken to prevent injury they can do many things that a normal person can do. Sport is encouraged so that muscles become stronger, which then protects the joints and decreases bleeding. Swimming and cycling are the two most recommended sports because they don't put pressure on the joints. Sports such as football, basketball, hockey, and lacrosse are off limits because the pose to much of a threat for injury. For moderate and severe types of hemophilia people have to take more precautions like not being in crowded of a place. People with severe hemophilia quality of life is not the same as a normal person because there is always the worry and fear that something could happen and if bleeding did occur there is only a short time frame for treatments to be made before the person can bleed out. Bibliography 1. Http://www.euronet.nl/~jonkr/, Ron Jonk-. "Hemophilia." University of Maryland Medical Center | Home. Web. 02 Mar. 2011. <http://www.umm.edu/altmed/articles/hemophilia-000076.htm>. 2. Question 679: Blood & Clotting Disorders and Hemophilia | Ask the Geneticist (SM)." Emory University Department of Human Genetics. Web. 02 Mar. 2011. <http://genetics.emory.edu/ask/question.php/679/Blood_&_Clotting_Disorders/1/Hemophilia>. 3. "Hemophilia - Genetics Home Reference." Genetics Home Reference - Your Guide to Understanding Genetic Conditions. Web. 02 Mar. 2011. <http://ghr.nlm.nih.gov/condition/hemophilia>. 4. "Hemophilia A (Factor VIII Deficiency)." Welcome to the National Hemophilia Foundation. Web. 02 Mar. 2011. <http://www.hemophilia.org/NHFWeb/MainPgs/MainNHF.aspx?menuid=180&contentid=45&rptname= bleeding>. 5. "Hemophilia - Genetics Home Reference." Genetics Home Reference - Your Guide to Understanding Genetic Conditions. Web. 02 Mar. 2011. <http://ghr.nlm.nih.gov/condition/hemophilia>.