Not too long ago (this year or 2009, perhaps) there was a story in the news about an analogous birth that occurred during the days of apartheid in South Africa. A white South African couple, i.e., both white, gave birth to a black baby girl. There was no evidence the white husband had been cuckolded by a black man, and both insisted that was not the case.
The little black girl (their daughter), however, was discriminated against in the apartheid schools where officials insisted she had to attend schools for black children.
Her white parents took their case to court, and argued their daughter should be treated as a white child and should be permitted to attend "white schools." Geneticists testified that there are so many black genes in the South African white population's gene pool that it is, in fact, possible for a white couple to give birth to a black baby without the husband being cuckolded by a black man. The geneticists also pointed out that although this is uncommon, this wasn't the first time it had happened.
The white parents won their case and their black daughter attended schools for white children.
The article at the link furnished by 4Julie apparently describes an analogous but inverse case.
