It's not good genes or genetics!!!
Here's a link to an amazing article by Lisa Wilson of the Raw Food Institute. Lisa uses both food and exercise to look like a supermodel, but I will tell you from personal experience that you will get to your ideal weight by eating raw and living foods! I don't go to the gym like Lisa does, I do light exercise at home, and I'm back down to the size I was when I was in my 20s.
I totally agree with Lisa's article, and so do Dr. Esselstyn, Dr. Campbell, and many, many more: we have 100% control over our bodies and our health. Don't blame it on genetics.