How do i change a sim's skintone colour genetically?

[M.M.A.A.]

hello, the question says it all, i have searched everywhere, everything that is mention is only about appearance, nothing is mentioned about genetics.

thanks in advance

[Mordant17]

You'll need to use SimPE (http://simswiki.info/wiki.php?title=SimPE) to edit the genetics.

[Mootilda]

Here's a tutorial. Unfortunately, the pictures are missing.
http://www.modthesims.info/showthread.php?t=56241

[M.M.A.A.]

i have SimPE, thanks everyone, ill try it out