ETX1, or Sushi-repeat containing protein, X-linked, is a human gene encoded by SRPX. It may also be known as: Sushi repeat-containing protein SRPX; DRS; HEL-S-83p; SRPX1. The encoded protein has an amino acid length of 464 and a mass of 51.6 kDa. Other isoforms may exist. Homologs of this gene exist in other organisms, including: Zebrafish, Frog, Chicken.