Stem cells have the ability to self renew, therefore they will not die off as soon as they are injected into the receiver (Gibbs). The research for stem cells is not easy. The process is complex and is very expensive. There are scientists all over the world studying and researching stem cells, this makes it harder to collect all of the outcomes (Walsh). There are two main types of stem cells scientists are researching: embryonic and adult stem cells. Embryonic cells come from taking tissue from an aborted embryo to get the proper materials needed for the study (Stem Cells: Pros and Cons). Adult cells come from placentas and umbilical cord blood. The adult cells were originally not expected to be very valuable. After testing the adult cells out, the results proved the scientists original thoughts wrong. Adult …show more content…
In August of 2001 President George Bush announced that federal money could go to researched working on already developed embryonic stem cell (ESC) lines. Among the scientists these lines were referred to as “presidential lines” because there are only 21 viable lines. With such a small number of lines it limits genetic diversity of the stem cells. This is a big problem because without genetic diversity how are the doctors and scientist suppose to help a specific person and their illness? Another problem with the presidential lines is, they are very old and they do not age up to expectations. Chromosomes in the cells go through some changes over time, which messes with the ability of the cell to stay “normal”. In all honesty the presidential lines are wasting the time of scientists and the government 's money. In 2006 President Bush vetoed the bill to expand funding for human ESC research. Scientists and doctors have been able to get around the presidential lines by using private biotech ways of funding. The people that have a different way of funding are free to create and destroy as many lines as they can