According to a study published in the journal Science, some Neanderthals had white skin and red hair. The study analyzes the only DNA gene of 50,000 year-old Neanderthals, the mc1r gene.
The current human being also has this gene and, in certain variants, the proteins that are generated have less functionality and these people have a whiter skin.
In the DNA of Neanderthals, a variant of that gene has been found that has never been identified in humans (the gene containing this variant has been searched in the DNA of 3,700 people and has not been found in any of them). And they have seen that the proteins that form when expressing it have the same functionality as those that occur in the expression of the gene itself of illegal people.