What specific gene interaction results in the Lavender or lilac hue in a Chihuahua?

Answer

Diluting 'D' gene acting upon chocolate genes

Lavender coloration is the result of the diluting 'D' gene acting upon the genes responsible for the chocolate color, yielding a distinctive, silvery-blue or purplish tint.

What specific gene interaction results in the Lavender or lilac hue in a Chihuahua?
rareDogtypebreedChihuahua