Failure to Replicate a Genetic Signal for Sex Bias in the Steppe Migration into Central Europe

Abstract

We fail to replicate a genetic signal for sex bias in the steppe migration to central Europe after ~5,000 years proposed by Goldberg et al. PNAS 114(10):2657-2662. Estimation of X-chromosome steppe ancestry in the Bronze Age central European population with the qpAdm method (Haak et al. Nature 522, 207-11) does not indicate lower steppe ancestry on the X-chromosome than in the autosomes. We perform a simulation which indicates presence of estimation bias of -19.5% in the inference of X-chromosome admixture proportions using the method used by Goldberg et al., largely eliminating the observed sex bias.