Which genes drive metabolism?

Reuters reported an interesting article a few days ago about researchers finding 4 genes that drive metabolism. The four genes FADS1, LIPC, SCAD and MCAD affect the metabolism by determining the rate in which individuals burn up food. These genetic variations could lead to personalized treatment for those who have susceptibility to obesity or coronary artery disease which have genetic components.

So this made me wonder. If you knew you had these genes and that your body would never be the "thin" (in your terms) ideal that you wanted, would you continue to pursue your efforts in trying to obtain it? Would it actually give you a sense of peace, knowing that you didn't have control over what your body did or rather would it make you feel worse, like your body was betraying you by having these certain genes?