Cres is an alias for the gene, Cystatin 8, in humans. Other names include: Cystatin-8; Cystatin-related epididymal spermatogenic protein; CRES; CTES5; cystatin 8 (cystatin-related epididymal specific). The encoded protein has an amino acid length of 142 and a mass of 16.3 kDa. Other isoforms may exist. This gene shares homology with other species, including: Rat.