Spanish researchers report that the Basque people, who are culturally distinct from other ethnic groups on the Iberian Peninsula, are not genetically distinct from them. Blogger Razib Khan notes that since the Basque language is unrelated to other European languages and since Basque people have higher rate of the Rh- factor, there have been many theories about where the Basques originate from. Khan adds that a recent study of the Y-chromosome R1b haplogroup suggests that the Basques are no different than other Europeans. And now in the journal Human Genetics, researchers used a dense, genome-wide SNP array to study differences between Spanish Basques and non-Basques. "Our analysis showed that, when a genome-wide perspective is applied, Basques are not particularly differentiated from other Iberian populations," the authors write, adding that the inconsistency "can be resolved if we consider that the polymorphisms accounting for most of this differentiation lie in genes such as ABO, RH, and the HLA complex that are, given their involvement in host-pathogen interactions, obvious targets for natural selection in the ancestral populations even at a microgeographic scale."