The Astrex coat results from a combination of the gene for the Rex coat (which is recessive) and another gene that causes the waviness. The name Astrex was coined because of a resemblance to Astrakhan, which is made from the hide of a newborn lamb. I don't know if the Astrex has ever been a recognized breed, but there are some breeds that may have the Astrex coat, the Harlequin being one of them. In the U.S, Harlies only have normal coats, but they historically also have Rex or Astrex coats in Europe. 20+ years ago, my very first pair of Japanese Harlequins gave me an Astrex baby in one of their litters; I have ocassionally seen Astrex Harlies in other places since then.