Twins with different color. Can anyone explain this please?

I just read this story about twins, born in Germany.
In this case, the kids are of different color. Black mother, and white father.

The page I read it from is not English in origin, but I guess the story is wide spread by now.

"During the development of the eggs with the mom, there can have been a mutation in the genes that descide the pigment of the skin. This genetical change can have happened to only one of the eggs, causing the twins to have different color of the skin." -says the doc.

My question is this, though..;
How does this mutation occur? Why, and how.

If anyone has any insight as to why this happened, please share, as I am very curious

[edit on 16-7-2008 by sweetalker]

Actually, twins can have different fathers. It's possible. Up to 14 days apart in some rare cases.

Some of these nurses and doctors were quoted "as ludacris" that the twins have different fathers.
But I personally dont have a problem believing that.

They will not be identical twins, and will look as much alike as siblings in general. So that actually makes it plausible, she may have been impregnated twice? (now offcourse twice in the given timeframe)

Or is that just something that dont happen. ??

[edit on 16-7-2008 by sweetalker]

they probably just inherited a different combination of traits from their parents.

consider the following:
Parent A and Parent B both have 1 white parent and 1 black parent - we'll not care about which trait each parent expressed, they could be both white, both black, whatever.

put each parent's traits on it's own axis in a table or grid as such - Parent A on top and Parent B down the side. the possible combinations of skin color can be determined:

------Wb-------wB

Wb---WW------WB

wB---WB-------BB

WW = white
BB = Black
WB = Tan?

so there's a 50% chance that the kid would be a mix of black and white, and a 50% chance that it would be fully either black or fully white.

i may not have that quite right, but i think i have the general idea. hope that helps.

[edit on 16-7-2008 by an0maly33]