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Recently, the debate on the origins of the major European Y chromosome haplogroup R1b1b2-M269 has reignited, and opinion has moved away from Palaeolithic origins to the notion of a younger Neolithic spread of these chromosomes from the Near East. Here, we address this debate by investigating frequency patterns and diversity in the largest collection of R1b1b2-M269 chromosomes yet assembled. Our analysis reveals no geographical trends in diversity, in contradiction to expectation under the Neolithic hypothesis, and suggests an alternative explanation for the apparent cline in diversity recently described. We further investigate the young, STR-based time to the most recent common ancestor estimates proposed so far for R-M269-related lineages and find evidence for an appreciable effect of microsatellite choice on age estimates. As a consequence, the existing data and tools are insufficient to make credible estimates for the age of this haplogroup, and conclusions about the timing of its origin and dispersal should be viewed with a large degree of caution. [ABSTRACT FROM AUTHOR]

Based on archaeological evidence, the spread of agropastoralism across Europe followed two main paths: the Danubian route, along which Neolithic farmers expanded north across the central European plains; and the Mediterranean route, where migration occurred along the coast of the Mediterranean sea. Here we examine 20 cattle breeds from the continent and assess the genetic diversity levels and relationships among the breeds using 19 microsatellite markers. Additionally, we show evidence that concords with two distinct cattle migrations from the Near East, and also demonstrate that Mediterranean cattle breeds may have had more recent input from both the Near East and Africa. [ABSTRACT FROM AUTHOR]