A genetic analysis by Gaku Tokuda and colleagues at the University of the Ryukyus in Okinawa , Japan , has provided some answers .
Japan /location/location/contains Okinawa
DT JJ NN IN NNP NNP CC NNS IN DT NNP IN DT NNP IN NNP , NNP , VBZ VBN DT NNS .
Japan
LOCATION
Okinawa
LOCATION
/location/location/contains