Because hemophilia is sex-linked disorder, it can be passed on from mother to child. This is because the gene responsible for making blood factors 8 and 9 are only found on the X-chromosome. If a female is a carrier that means that she has one bad gene and one good gene for this disease. There is a fifty percent chance that she would pass it on to her child because she can only pass on one of the two chromosomes. If a male has hemophilia, he will have normal sons and all of his daughters will be carriers of the hemophilia disorder because all he can pass on is the defective X-chromosome.
Hemophilia is a rare genetic blood clotting disorder that primarily affects males. People living with hemophilia do not have enough of, or are missing, one of the blood clotting proteins naturally found in blood. Two of the most common forms of hemophilia are A and B. In persons with hemophilia A (also called classic hemophilia), clotting factor VIII is not present in sufficient amounts or is absent. In persons with hemophilia B (also called Christmas disease), clotting factor IX is not present in sufficient amounts or is absent.
Hemophilia carried in a recessive X-linked pattern in the X chromosome. Specifically, hemophilia A is found in the F8 gene, while, hemophilia B is found in the F9 gene. If a male has an X chromosome carrying the faulty gene then the male will have Hemophilia. However, if a female has the faulty gene she will only carry the disease, unless, both her father and her mother have the faulty gene. Women don’t usually have hemophilia because they have enough normal clotting factors in their unaffected X chromosome.
Adrenoleukodystrophy Adrenoleukodystrophy is a genetically transferred disease which causes the human body to not be able to breakdown “very-long-chain-fatty-acids” (VLCFA). This inability to break down these acids eventually leads to myelin deterioration as well as the deterioration of the nervous system. Although there is no cure for this terrible disease, there are a variety of effective treatments. Adrenoleukodystrophy is a sex-linked trait carried on the X-chromosome and is carried by the mother. It is only passed on to male children, and every male child that a carrier mother gives birth to has a fifty-fifty chance of acquiring adrenoleukodystrophy.
Not only this, but we need to know there are 2 types of hemophilia, hemophilia A, and hemophilia B. To begin, lets find out how Hemophilia A and B are different. Hemophilia A is more common than B, but they both have similar symptoms and treatments. 1 in 5,000 males worldwide are born with hemophilia A and 1 in every 20,000 has hemophilia B (“Hemophilia”). Hemophilia is an X-Linked recessive pattern, which means it is passed down from a mother, who is a carrier of the trait, to a son, and each of the sons would have 50% chance of getting hemophilia.
About eighty percent of all cases of hemophilia have an identifiable family history of the disease; in other instances, it may be attributable to a spontaneous mutation. Researchers recently discovered that the spontaneous mutation of the factor VIII gene in two children was due to the attachment of a foreign "jumping gene" that disrupted the blood-clotting ability of the factor VIII gene. Inheritance is controlled by a recessive sex-linked factor carried by the mother on the X chromosome. A probability of one in two exists that each boy born to a normal male and a carrier female will be hemophiliac and the same chance that each girl of this union will be a carrier. Of the children of a hemophiliac male and a normal female, all the girls will be carriers and all the boys will be normal.
A very daughter of a man with hemophilia will be a carrier (Obliogate carrier). If a man with hemophilia has a son, they will not be affected and will not have hemophilia. However, approximately 30% of those families affected by hemophilia have no previous family history of hemophilia and is considered a “spontaneous mutation” (“Hemophilia”2002). There are degrees of severity to the amount of specific protein in the blood. Normal levels of the factor proteins measured in the lab range approximately 50%-150%.
Duchenne muscular dystrophy is a neuromuscular condition. It is the most common type of MD Duchenne Muscular Dystrophy. (DMD) is an X-linked disorder which affects about 1 in 3,500 males. Females are usually carriers of the defective gene that causes the disorder. Under Mendelian inheritance, when a mother carries the defective gene, her female child will have 50% chance of being a carrier and her male child will have 50% chance of having the disease and showing the symptoms.
SCD is an inherited, autosomal recessive genetic defect. Individuals who have the disease inherit two defected genes — one from each parent. With each pregnancy the risk of having a child born with SCD is 25%, if both parents have the trait (Blackwell, 2011). If a child inherit a sickle hemoglobin gene only from one parent and a normal gene from the other parent, have sickle cell trait. In this case, body make both sickle hemoglobin and normal hemoglobin, so they usually have few, if any, symptoms.
If a male receives an X chromosome with the defect, he will be hemophilic. If a female receives an X chromosomes with the defect, her other X chromosome would dominate, leaving the female as a carrier of the gene (Carriers, “Individuals who have only one copy of the recessive, disease causing allele for a particular genetic disease). To run the point home, the son of a mother who carries of the gene and an unaffected (Unaffected Individuals, “Individuals who do not have an allele for a particular genetic disease) father is 50% likely to suffer with Hemophilia. While the daughter is 0% likely to be affected and 50% likely to carry the gene. The only way a female could be affected by Hemophilia is if both her mother was a carrier or affected by the gene and her father had the defect.