Monday, October 26, 2009

Down Syndrome and SCR

Mutations are a sudden departure from the parents in one or more characteristics. Mutations cause disorders by adding, deleting, or extending a gene strand. These disorders can be large or small depending on how much of the DNA is changed.
There are four types of inheritance patterns: autosomal dominant, autosomal recessive, x-linked recessive, and x-linked dominant. Autosomal dominant is when the inheritor has a 50/50 chance of receiving the mutated gene. This is because the carrier only has one copy of the mutant allele and one normal copy. Autosomal recessive is when the inheritor only has a 25% chance of inheriting the mutation because the disorder is only inheritable if there are two copies of it. If there is only one copy of the gene the inheritor is only a carrier of the gene but is not affected by it. X-linked recessive inheritance is a something that is more likely to infect a man because they only have one set of the gene they will automatically be affected by the mutation because they do not have an extra copy. X-linked recessive inheritance also can only be passed from male to female but from female to male and female. Females are very likely to not get a X-linked recessive disorder because they need to have two copies of it for the mutation to have an affect. X-linked dominant inheritance is more likely to affect the female because there is not transmission from father to son and automatic transmission from father to daughter. There is only a 50% chance of a mother passing it on also.
Down Syndrome is a genetic disorder that is caused by extra material added to the 21st chromosome. There are no environmental factors that can lead to the disorder of Down Syndrome. Recently they have found a shot that can be given to relieve some symptoms, but it has only been used on test mice. It is not yet known whether it will work on human beings. Not a whole lot of research has been happening with Down Syndrome lately; scientists believe that it is too complex of a disorder to have a cure be found. Down Syndrome causes a flat facial profile, squinty eyes, heart problems, low muscle tone, slower growth rate, and learning disabilities. Stem Cells are cells that haven’t committed to a specific type of cell yet. The hope for them is that if they replace them with other cells in the human body they will be able to heal and help different health problems. It is controversial because they use unborn babies as test subjects. That kid will never have a chance to live a life, and it was born for purely research purposes. It almost lowers the value of human life. I do not think that it should be legalized for the simple fact that it’s killing babies. All humans should have the right to live a normal life, and stem cell research can take that away. There is a chance that stem cell research could find a way to replace the missing chromosome from a down baby, but I don’t think it’s worth killing another one.