When we think of great scientific advancement, we usually call up a stock-image montage of great discoverers like Archimedes, Galileo, or Marie Curie, of Isaac Newton contemplating the laws of gravity, of Jonas Salk’s polio vaccine, and NASA sending a man to the motha-effin’ moon".
What we don’t think of as a huge moment is that day when a bunch of people figure out what makes a pig a pig. Nevertheless, that day came this week, and it’s kind of a big deal.
It goes like this: The Swine Genome Sequencing Consortium (SGSC) recently finished a complete genetic sequence of the domestic pig – whom they for reals named TJ Tabasco – and what they’ve turned up may well have profound meaning even for those of us living the non-barnyard life.
Led by scientists from the University of Illinois, the University of Edinburgh in Scotland, and Wageningen University in the Netherlands, the group compared the DNA of Mr. Tabasco as well as a number of his clones to that of many farm-animal friends, including that of a horse, cow, mice, wild boar and even to human DNA. The full scope of this project could have a significant impact on human medical research.
As with teenage boys, pigs get a bad rap for being dirty and constantly eating, but they actually share a great number of physical characteristics with humans, especially organs like our eyes, our gastrointestinal tract, and our metabolism, making them an ideal animal to use and study when we are looking for insight into human health and disease. In fact, when studying the cause of a particular kind of human blindness – retinitis pigmentosa – researchers routinely use pigs to model the disease and its symptoms.
The study showed that there are 112 shared aberrations in both pig and human DNA, findings which could shed light on conditions from obesity and dyslexia to Parkinson’s or Alzheimer’s. And though animal activists won’t be pleased, the fact that pigs have such significant commonalities with humans could help predict how effective medical drugs are as they go through trials for human use.
Researchers say their findings could lead to using pigs for other kinds of medical purposes as well. This knowledge may allow scientists to build pigs that are designed to grow human organs for transplantation, including hearts and liver, for human patients. According to Nature, "pig organs are roughly the right size, and researchers hope to create transgenic pigs carrying genes that deceive the immune system of recipients into not rejecting the transplants.” For the many people stuck on organ transplant lists, custom pig organs could be a saving grace.
The group also was able to determine our common piggie’s evolutionary path back to where its lineage split into Asian and European varieties some 800,000 to 1.6 million years ago, probably as humans in different parts of the globe began to domesticate them. Additionally, researchers identified specific genes and the purposes they serve. For instance, they identified those that contribute to pigs famously good olfactory senses, but also the relatively few genes controlling taste, which leaves their taste reception relatively poor.
Obviously the SGSC findings also are significant for agricultural and livestock industries, as raising pigs is a valuable/delicious economic livelihood. Researchers found that the genes controlling immune system response in the domestic porker is evolving rapidly, which could either be related to, or have an effect on, livestock antibiotics. Sonny Ramaswany, head of the Dept. of Agriculture National Institute on Food and Agriculture said, “This new analysis helps us understand the genetic mechanisms that enable high-quality pork production, feed efficiency and resistance to disease…It can ultimately help producers breed high-quality swine, lower production costs and improve sustainability.”
So what have we learned? To borrow from Homer Simpson, bacon is both the cause of and solution to so many of our health problems. But, if pigs really are so close to humans, maybe we shouldn’t be eating bacon at all.