The Globe and Mail reports in its Friday edition that a rise in Japanese government bond yields and the related shifting makeup of foreign holders of U.S. government debt could have a far-reaching impact with implications for Canadian investors. The Globe's Andrew Galbraith writes that for decades, low interest rates in Japan forced Japanese insurers and pensions to look overseas for higher-yielding assets -- mostly U.S. Treasury securities -- to match their long-term liabilities. Now, lifted by expectations of Japanese economic growth and the return of inflation after decades of stagnation, as well as concerns over rising public debt levels, yields on Japan's government bonds are increasingly attractive for long-term investors. That has the potential to remove a stable, less cost-conscious buyer from the U.S. Treasury market, said Tiago Figueiredo at Desjardins, pushing global bond yields higher and boosting market volatility. Higher benchmark bond rates could hit Canadian mortgages. RBC's George Davis said rising U.S. debt levels and eroding confidence in U.S. policy mean that the investors replacing Japanese insurers "will likely demand additional protection for their purchases -- in the form of higher yields."