A recent study finds Amerindian mitochondrial DNA haplogroups predominate in the population of Argentina:
Amerindian haplogroups were most frequent in the north and south representing more than 60% of the sequences. A slightly different situation was observed in central Argentina where the Amerindian haplogroups represented less than 50%, and the European contribution was more relevant. [. . .] A minor contribution of African lineages was observed throughout the country.Autosomal evidence indicates Argentinians harbor substantial Amerindian and minor African admixture.
Regarding autosomal evidence of admixture, the relative European, native American, and West African genetic contributions to the gene pool of La Plata were estimated to be 67.55% (+/-2.7), 25.9% (+/-4.3), and 6.5% (+/-6.4), respectively.Argentina is generally perceived to be the whitest country in Latin America. See Brazilian or Puerto Rican "whites" if you require further evidence "white" doesn't have the same meaning in Latin America as it does in America.