What is needed is a redefinition of "money of account" for the digital age.

Coinage Act of 1792:

"the money of account of the United States shall be expressed in dollars or units … of the value [mass or weight] of a Spanish milled dollar as the same is now current, and to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure … silver."

BTW, It is not a sub-committee of trade or finance that is needed to look at this, but an amendment to the Constitution.