EXPAND1 is an alias for the gene, Melanoma associated antigen (mutated) 1, in humans. Other names include: PWWP domain-containing protein MUM1; Mutated melanoma-associated antigen 1; MUM-1; Protein expandere; HSPC211. The encoded protein has an amino acid length of 710 and a mass of 78.6 kDa. Other isoforms may exist. EXPAND1 is a member of the MUM1 family. This gene shares homology with other species, including: Mouse, Rat, Frog, Chicken.