Due to US sanctions , Russia may well start to invest its reserves in Bitcoin. Ive heard this rumour for months, but it looks more and more logical and likely.
Countries who have sanctions could make use of bitcoin to overcome those restrictions and countries like Iran, Russia and many other countries could take advantage of that and have a trade with other countries, i am not sure how they will replace the entire dollar reserve which is not a smart move in any way but then looking forward if there is a reserve for the virtual currency, then it will be a good move to over come those restrictions.