Rules
Expressed Genes:
Reversal: _+r _+r

Reversal is a modifier that attaches itself onto several markings, such as Marozi and Point.

Reversal changes a marking that is normally darker than the base coat to be lighter than the base coat. The affected marking must still be from the base coat family of the colonist, unless of course Artifice is in play on the marking.

For the sake of gene modifications, reversal counts as an entire allele and cannot be added if the allele is also being changed. In other words, you cannot change zeb zeb to Zeb+r zeb in one use of Dice. It does not count as an additional marking for the Immigration Center.
Good in-game examples