Q6, or Quiescin sulfhydryl oxidase 1, is a human gene encoded by QSOX1. It may also be known as: Sulfhydryl oxidase 1; Quiescin Q6; hQSOX; thiol oxidase 1; QSCN6; quiescin Q6 sulfhydryl oxidase 1. The encoded protein is an enzyme with an amino acid length of 747 and a mass of 82.6 kDa. Q6 is a member of the Quiescin-sulfhydryl oxidase (QSOX) family. Homologs of this gene exist in other organisms, including: Mouse, Arabidopsis.