I need your comment on each of my classmate answer on our discussion. Please let be specific on what number you answer.
- One of the causes of chromosomes mutation is inversion. This occurs when an area of DNA on a chromosome flips its orientation with regard to the remainder of the chromosome. If chromosome 16 is affected by just one inversion it can cause leukemia. If inversion leads to an embryo having too few or too many copies of genes, the embryo can miscarry, fail to grow, or be born alive with substantial medical problems.
- One disease that is caused by chromosomal mutations is phenylketonuria. This disorder increases the levels of phenylalanine in the blood. Phenylalanine is a building block of proteins and too much of it can cause intellectual disability. Mutations in the PAH gene cause phenylketonuria. The PAH gene helps to make phenylalanine hydroxylase. If phenylaline is not processed by the body correctly, it builds up and can eventually cause severe brain damage and other serious complications.
- Cri-du-Chat Syndrome is caused by a deletion of the top portion of the fifth chromosome. This mutation usually occurs during “S” phase of meiosis. This means that either a sperm or a egg cell will be mutated causing Cri-du-Chat Syndrome to develop during fertilization. One of the major symptoms of Cri-du-Chat Syndrome is a cat-like cry that comes from patients, which is caused by the larynx not forming properly. Additionally, someone with Cri-du-Chat Syndrome will have several prominent features such as a small head or widely set eyes. Occasionally, those with Cri-du-Chat Syndrome can develop skeletal and muscular defects causing them to have difficulty talking or walking.