Into the origin and diversification of Podolian cattle breeds by testing
Neolithic scenarios of European colonization using genome-wide SNP data
Abstract
Together with the Neolithic human expansions, cattle spread from
domestication centres and colonized the world. During their tangled
expansion dynamics, European cattle occasionally intermingled with local
aurochs leading to an exclusive pattern of genetic diversity. Among the
most ancient European cattle, are breeds belonging to the so-called
Podolian trunk which their history is still not well established. Here
we used genome-wide SNP data of 806 individuals belonging to 36 breeds
to reconstruct the origin and diversification of the Podolian cattle and
to provide a reliable scenario of the European colonization, through an
Approximate Bayesian Computation approach. Our results indicate that
European Podolian cattle displays higher values of all genetic diversity
indices when compared to both African taurine and Asian indicine. All
our clustering analyses show close genomic relationships among Podolian
breeds suggesting their possible common genetic ancestry. When we
simulated and tested scenarios of colonization, we found that Podolian
cattle followed different colonization routes, in line with two
principal human migrations: via the Danube during the early stages of
the Neolithic farmer expansions and through sea routes likely during the
pre-Etruscan period. Furthermore, the best fitting model indicates that
these two genomic pools admixed in Italy suggesting the Peninsula as an
important hub for the Podolian cattle.