I recommend USA. Study bioinformatics in U.S. universities and colleges may differ from those in your home country in several ways. For one thing, competative research lab, small class sizes are very common. There may be as few as 10 to 20 students in a class, giving you the personal attention you need in order to succeed. While in class, students are encouraged and expected to contribute to the discussion. Studying in the U.S. gives you the opportunity to gain a mentor in your given career field, an invaluable resource.