High Level Synthesis (HLS)is a designing methodology aimed to the synthesis of RT-level hardware devices from behavioral development specifications. In this work we present an evolutionary algorithm in order to optimize circuit specifications by means of a special type of genetic operator. We have named this operator algebraic mutation, carried out with the help of algebraic equations. This work can be classified within the development of an automatic tool of Formal Synthesis by using genetic techniques. We have applied this technique to a simple circuit equational specification and to a much more complex algebraic equation. In the first case our algorithm simplifies the equation until the best specification is found and in the second a solution improving the former is always obtained.