You can rest assured that there is NO genetically modified pork available on the market. I'm told that pork, and meat products in general, are stuffed full of hormones. As far as pork is concerned, there are NO hormones licensed for pork production. A very good question. This is because a bacterium in meat is found predominantly on the meat's surface.
Ground meats have a huge surface area compared to solid cuts, and they have been handled more often.
Play safe, and cook all ground meat products to well every time.