I’ve read the material about the background that you’re looking for, and I have some of the background (in biochemistry/biology, or computing science, or mathematics/statistics) but I’m missing one of those areas. Should I apply?
That depends. If your academic record is very good, and you have most of the background, the program can offer you the opportunity to learn the rest. Each application is considered on a case-by-case basis by the faculty, so we cannot tell you if you will be accepted until you send in your full application.