This is untrue.
Though the Voters Rights Act was established to provide fair voting rights for all Americans. the 15th ammendment affirmed this just after the Civil War. The 15th Amendment is in the Constitution which can not be eliminated or finished after 2007 unless it is Ratified by Congress.
As we all know Jim Crow laws prevented Blacks from voting with several tests and other barriers. The Voters Rights Act of 1964 signed by Pres. Lyndon Johnson disallowed the practice of Jim Crow or other barriers that prevented Americans from voting. Since then,there have been various laws and acts enacted by Congress and local government from preventing people from voting for any reason regardless of race.
The 15th Amendment states:
Section 1.
The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude
Unless the Constitution is ratified to change this, BLACKS WILL NOT LOSE THE RIGHT TO VOTE!
Sorry, I have heard this rumor a thousand times. A little historical research goes a long way

As you probably noticed I'm a constitution buff.