Monstrous but Valyrian

I seem to remember reading that the Mantaryans perhaps had the repuation as a city of monsters because of defects brought about by a mass amount of inbreeding after the fall of Valyria, if that was the case then the Mantaryans as many defects as they may have should look like High Valyrians (or Essosi Valyrians) but in mod they are similar to the Tolosi and Elyrians in that they can have other hair and eye colours.