Hemophilia Research Paper

Abigail McWilliams

Ms. Castle

Pre-AP Biology

April 17, 2017

Genetics Research Paper Intro Hemophilia is a sex-linked disorder that causes blood clotting. “A person is lacking proteins called “clotting factors” and the blood doesn’t clot properly as a result. This leads to excessive bleeding.”(Healthline Media) Common symptoms of hemophilia can be bleeding easily; the blood takes a longer time to clot after an injury so you bleed longer and more. Hemophilia can also cause internal bleeding. The internal bleeding can bleed into the joints and cause swollen joints. Other symptoms can be blood in urine, deep and large bruises, excessive bleeding, pain in joints, tight joints. Hemophilia has a large effect on the joints in your body. “When

There are two types of hemophilia the most common being hemophilia A and then hemophilia B. “Hemophilia A is the most common type of the condition; 1 in 4,000 to 1 in 5,000 males worldwide are born with this disorder. Hemophilia B occurs in approximately 1 in 20,000 newborn males worldwide.” according to Genetics Home Reference. Males are more prone to get the disease because they only have one X chromosome and not two like females; so men do not have the “backup chromosome” that females have. “Because it is unlikely that females will have two altered copies of this gene, it is very rare for females to have hemophilia. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.” says the US National Library of

It is a sex-linked trait. Both hemophilia A and B are inherited in an X-linked recessive disorder. The mutation would then have to happen in both X chromosomes for a girl to have hemophilia. For a boy to have Hemophilia the X chromosome would have to be dominant because males only have one X chromosome, so it is more likely for males to have hemophilia and they can’t be a carrier for the disease. A daughter however has two X chromosomes and can either be recessive and not have hemophilia, heterozygous or be a carrier for hemophilia, or homozygous recessive. Children’s genes depend on what their parent’s genes