Japan’s parliament enacted changes to the imperial succession law yesterday but maintained the bar on a woman becoming emperor despite surveys suggesting wide public support for the idea.

The future of the imperial household -- mythically descended from the Shinto sun goddess Amaterasu -- hinges currently on Prince Hisahito, the 19-year-old nephew of serving Emperor Naruhito, 66.

If Hisahito -- barely out of school and currently studying biology and insects and who is not married -- has no son, then under the rules as they stand he will have no heir and the bloodline will end.

The bill allows the adoption of male distant relatives over 15 back into the imperial family -- as long as they are single.