Skin color comes from the interaction of at least four genes, likely more.
Generally, the genes that lead to darker skin color are dominant over the genes that lead to lighter skin color. However, this is not true for all the genes. If it were, then a Black man with only dark genes would have children that looked the exact same color as him no matter what color his wife is. Obviously this isn't the case.
In reality, most people have some mix of skin color genes, even if it doesn't show (a recessive gene won't show if you have only one of them). So two people with darker skin can have a light-skinned baby if their recessive light-skinned genes happen to configure that way.
None of this has anything to do with any other genes, just those handful that have to do with skin color.
Generally, the genes that lead to darker skin color are dominant over the genes that lead to lighter skin color. However, this is not true for all the genes. If it were, then a Black man with only dark genes would have children that looked the exact same color as him no matter what color his wife is. Obviously this isn't the case.
In reality, most people have some mix of skin color genes, even if it doesn't show (a recessive gene won't show if you have only one of them). So two people with darker skin can have a light-skinned baby if their recessive light-skinned genes happen to configure that way.
None of this has anything to do with any other genes, just those handful that have to do with skin color.