Every single hamster in the United States today comes from a single litter captured in Syria in 1930

Although the Syrian hamster or golden hamster (Mesocricetus auratus) was first described scientifically in 1839, researchers were not able to successfully breed and domesticate hamsters until 1939. The entire laboratory and pet populations of Syrian hamsters appear to be descendants of a single brother-sister pairing. These littermates were captured and imported in 1930 from Aleppo by Israel Aharoni, a zoologist of the University of Jerusalem. In Jerusalem, the hamsters bred very successfully. Years later, animals of this original breeding colony were exported to the USA, where Syrian hamsters became one of the most popular pets and laboratory animals. Comparative studies of domestic and wild Syrian hamsters have shown reduced genetic variability in the domestic strain. However, the differences in behavioral, chronobiological, morphometrical, hematological and biochemical parameters are relatively small and fall into the expected range of interstrain variations in other laboratory animals.