Why should everyone know a little about genetics?

Most of your physical traits, such as eye color, hair color, and height, are inherited. So, too, are risks for health problems and all diseases or medical conditions (except trauma). 

By knowing a little about genetics, you will understand how variations in your DNA may affect your health. You may also learn what health problems you may be at increased risk for in the future and how to reduce your risks. 

What are the top six things everyone should know about genetics?