Did you know that at this time in the USA about 75,000 people are in need of a organ transplant. Imagine for a second, how many lives could be saved if we only had more organs to give to patients in need of a new one. The problem is there are not enough people willing to donate them. But within a few years scientists may have discovered a new source for them. Since March of 2000 scientists have been hopeful that genetically altered pig organs could one day take the place of dysfunctional human organs. In 1984 a newborn pig named "Baby Fae" lived an additional 20 days with a heart from a baboon. This piece of evidence just shows that this process can be done with several changes and tests.
The reason why scientists chose pigs is because pigs have organs similar in shape, size, and function to human organs. However this process is not as easy as you may think. Pigs organs contain 2 genes called GGTA1. This gene is responsible for the production of a sugar called alpha 1, 3-galactose. If a doctor was to transplant a foreign organ into a human body the body's immune system would identify alpha1, 3-galactose as a enemy and attack it as if it was a pathogen from which the body must be protected. Within minutes the organ would turn black and it would die. To prevent that from happening, scientists need to find a way to clone pigs that do not contain these genes. Scientists have already made a big step toward that goal. Scientist were able to clone pigs that lack one of two copies of GGTA1, the gene responsible for the production of alpha 1, 3-galactose. Without the sugar in the organ the human's immune system wouldn't sense it and wouldn't attack the organ.
For this gene knockout procedure scientists injected DNA which was meant to disrupt the GGTA1 gene into fetal pig cells. The cells that took up the DNA were then identified, isolated, and inserted into early pig embryos. These were then implanted into pig mothers for delivery.
