There are many human characteristics and diseases that are directly inherited by the rules of Mendelian genetics (for example, Duchene's muscular dystrophy is a disease that is inherited as an x-linked recessive, and ABO blood groups are inherited as a co-dominant trait). These are traits or diseases that occur because of variations in a single gene.  However, there are many diseases and human characteristics that although not inherited in a direct Mendelian fashion (i.e. they are not the result of a difference in a single gene), clearly seem to have a genetic component to them. These genetic components are also strongly influenced by environmental factors. It is the interaction of "nature" (genetic factors) and "nurture" (environmental factors) that determine the resulting trait. Some examples of these might be type 2 diabetes (a disease) or intelligence (a human characteristic). For this exercise, choose a disease or normal characteristic and research the contributions of genetics and environment on the development of this trait. Your topic cannot be a characteristic or disease caused by a single gene, or by a chromosome defect (e.g. Down's syndrome).

Choose topic. List three.