It is my opinion that the myths and customs flow would be going from the east to the west instead of the other way. The customs may have originated in Japan.
Read This book by Stephen Oppenheimer.
Eden in the East
The Drowned Continent of Southeast Asia
The biblical flood really did occur - at the end of the last Ice Age. The Flood drowned for ever the huge continetal shelf of Southeast Asia, and caused a population dispersal which fertilized the Neolithic cultures of China, India, Mesopotamia, Egypt and the eastern Mediterranean, thus creating the first civilizations. The Polynesians did not come from China but from the islands of Southeast Asia. The domestication of rice was not in China but in the Malay Peninsula, 9,000 years ago.