Polygenic traits are traits determined by the combined effect of more than one pair of genes. Human stature is an example of this trait. The size of all body parts from head to foot combined determines height. The size of each individual body part are determined by numerous genes.
Although you don't necessarily have to major in interior design, a bachelor's degree or higher in the discipline provides the best foundation for a career, according to the Foundation for Interior Design Education and Research.
If you plan to become a professional curriculum designer, you will generally need to have a teaching degree and a master's degree in education. If you want to remain a teacher and design curriculum for your own students, look into continuing education courses that can help you get started.