@Anon
Forgive me, but I was so curious I looked it up myself. From Wikipedia's article on H. Denisova:
"According to recent genetic studies modern humans may have mated with "at least two groups" of ancient humans: Neanderthals and Denisovans. Genetic study indicates approximately 4% of the DNA of non-African modern humans is the same as that found in Neanderthals, suggesting interbreeding. Tests comparing the Denisova hominin genome with those of six modern humans: a !Kung from South Africa, a Nigerian, a Frenchman, a Papua New Guinean, a Bougainville Islander and a Han Chinese showed between 4% and 6% of the genome of Melanesians (represented by the Papua New Guinean and Bougainville Islander) derives from a Denisovan population. This DNA was possibly introduced during the early migration to Melanesia.
Melanesians may not be the only modern-day descendants of Denisovans. David Reich of Harvard University, in collaboration with Mark Stoneking of the Planck Institute team, found genetic evidence that Denisovan ancestry is shared by Melanesians, Australian Aborigines, and smaller scattered groups of people in Southeast Asia, such as the Mamanwa, a Negrito people in the Philippines. However, not all Negritos were found to possess Denisovan genes; Onge Andaman Islanders and Malaysian Jehai, for example, were found to have no significant Denisovan inheritance. These data place the interbreeding event in mainland Southeast Asia, and suggests Denisovans once ranged widely over eastern Asia."
So I was correct, after all: African peoples do not have any notable percentages of H. Denisova or H. Neanderthalis blood whatsoever, rendering this racist's argument spectacularly, hilariously wrong.