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.
Get training. You won't have to have a degree to work as an interior decorator, but some classes or certifications can give you greater credibility. Many community colleges offer associates degrees, and colleges often have certification programs or short courses on interior design.