Scientists at the University of Wisconsin-Madison are also exploring ways to customize pigs to address other medical problems. The scientists are using gene editing to create pigs with gene mutations that cause the disease neurofibromatosis type 1, or NF1. Around one in 3,000 babies in the U.S. is born with the condition, which can cause tumors on nerve tracts in the skin and eyes, learning disabilities and gastrointestinal problems.