From Leopard Gecko Wiki
Mack Pastel History
The Mack Pastels are considered a by-product of the Mack Snows. They first started popping up randomly in colonies when the Mack Snows were released.
Mack Pastel Description
When Mack Pastels hatch, the first colored area after the neck band is white and the body areas are yellowish where they would be white or bright yellow. Please see the picture to the right to see a Mack Pastel Albino.
Mack Pastel Genetics
Alex Hue has proven the Mack Pastels to be Dominant genetically.