What is the difference genetically between a F1 savannah cat & a F2 Savannah cat?

The main difference between an F1 Savannah cat and an F2 Savannah cat is the amount of wild serval blood in each generation. An F1 Savannah cat is the first generation offspring of a Serval, usually a Serval father and a domestic mother, and is considered to be 50% wild. As the filial number increases (F2, F3, etc.), the measure of wild blood (serval DNA) decreases; the more closely related a Savannah cat is to the serval cat, the rarer it is. F5, F6, and F7 cats are increasingly common as the breed increases in popularity.