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.
In order to get certified as an interior designer in California, you must have a combination of both education and experience. Option 1 is to have completed a 4-year interior design bachelor program and have 2 years of experience working as an interior designer.