Genetic Diseases

A genetic disease is caused by the occurrence of a negative genetic mutation. A mutation is the change in the bases of the A,T,G,C in DNA. A base can be added, deleted, or substituted. Mutations are cause by mutagens, which are factors in the environment such as: cigarette smoke, radiation, and pesticides.Negative mutations are those that affect your well being in a harmful way. A few genetic diseases are: Down Syndrome, Hemophilia, and Cystic Fibrosis. Each of these diseases occur in a different way and some are inherited.

Down Syndrome is a chromosome mutation which ninety five percent of the time is caused by an additional twenty first chromosome. People living with Down syndrome appear differently than others in which they are shorter and their facial features are distinctive. Also, with this disease you are more likely to develop heart defects and diseases such as leukaemia and Alzheimer's. Because of these diseases and heart defects being likely,people living with Down syndrome will have a shorter lifespan. Along with diseases, they also have mental delays causing them to need come extra help through care givers. Down syndrome is not inherited. 

Hemophilia, unlike Down syndrome, is commonly hereditary. It is caused by a defect in the gene that decides how your body will produce blood clotting factor. Because of this defect, you will have little to no clotting factor. This makes your blood unable to clot,  causing you to bleed very easily. People living with hemophilia have to be careful to not get injured because this could cause them to bleed. Also, regular trips to the doctor are necessary to receive transfusions of clotting factors. People living with hemophilia will have a shorter lifespan as well. 

Cystic Fibrosis is disease that is caused by more that thirteen hundred mutations in one gene. The mutations cause a protein that is supposed to carry chloride ions into and out of cells to be made incorrectly, causing the level of chloride ions to be flawed. Because the levels are incorrect, mucus inside of the lungs is too thick making breathing a challenge. This mucus buildup also blocks pancreatic juice from flowing to the small intestine, making the body unable to break down food.  People living with cystic fibrosis are required to take medication daily and go to physical therapy to avoid lung infection.

Example of a genetic mutation involving substitution (http://mrsgsbiologyclass.edublogs.org/files/2013/03/DNA-Mutation-148mrie.gif)