The next time you find yourself scarfing down food at an all-you-can-eat buffet and your friend calls you a pig, there may be more truth to that statement than you think. It’s not merely our appetites that we have in common with these animals, but a portion our DNA.
Given that pigs and humans are both mammals, we share a certain amount of genes with these curly-tailed animals. It would be misleading, however, to try to assign a certain percentage in regards to exactly how much we have in common DNA-wise with pigs. To do this accurately, we need to compare the more precise attributes that we share. For example, the protein-encoded portion of our DNA is the same as many different mammals. This portion only makes up one to two percent of our entire DNA. As you can tell, it is not simple to state an accurate percentage of commonality between mammals.
The protein-encoding portion of DNA is actually easier to compare between mammals than other portions because they evolve quickly. While humans and pigs do share portions of DNA, they aren’t so closely related that DNA is simple to compare. It is easier to relate primates and humans because the sequences are closer together. By the time sequences of human and pig DNA could be associated, so much movement and change has occurred that they don’t even resemble each other enough for a valuable comparison. This brings us back to the initial point that an overarching comparison between what makes up humans and pigs isn’t practical.
There are studies being done now regarding how well humans can accept organs or tissue from pigs. The results have been satisfactory. Many people believe that this is because the pattern of our DNA is the same. However, some work to the pigs’ organs/tissue is done by scientists before implantation into a human. A main difference between humans and most other mammals is a gene called galactotransferase. Most mammals, except humans and some apes, have this gene. Galactotransferase surrounds all of a pigs’ cells with an antigen. Thus, if untouched organs from a pig were implanted into a human, the human body would reject it because of this antigen. Therefore, scientists have been genetically modifying pig test subjects to remove the galactotransferase gene so that pigs and humans can share organs.
When comparing humans and pigs from a different perspective than DNA, some of our behaviors are the same. A study reported that pigs can be influenced by food and wind up domesticated in many instances. Sound familiar? This same study also determined that pigs have the same protein malfunctions that cause diseases like Alzheimer’s and Parkinson’s. More than just an interesting fact, because this means that pigs could prove very useful to humans as we search for cures to diseases like the ones mentioned above.