retrovirus

There also are fears that pig organs may carry viruses (such as porcine endogenous retro-viruses (PERV), a leukemia-like disease found in pigs) that can't be treated in humans.

no scientific research shows that these crops are safe for human consumption in the long term, whereas there is research warning of dangers of cancer, of retro-viruses (like Aids), of anti-bacterial resistance and other risks of splicing viral and bacterial DNA into plants;