The Reticulum galaxy is the galaxy in which the Reticulans, or "Greys," reside, presumably on the planet Reticulum. When winding up FBI Agent Tom Colton in 1993, Special Agent Fox Mulder claimed that the Reticulum galaxy was depleted of iron and that this was the cause of the Reticulians' grey appearance. (TXF: "Squeeze")

In real life, it is believed that the Grey aliens come from the Zeta Reticula star system, which is in our galaxy. The idea that the entire galaxy is depleted of iron is very unlikely.